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PubMed2006

The validity of clinical measures of patella position.

Patellar taping is regarded as an important element of the treatment of patellofemoral joint pain. Key to the successful use of patellar taping is the assessment of patella position. The reliability and validity of the techniques used to assess patella position has been questioned. The aim of the study was to assess the validity of the clinical assessment technique of patella medio-lateral position and patella lateral tilt against the criterion measure of MRI. Twenty-four subjects eight females and 16 males had their patella position examined in the study (mean age 24.5+/-7.9 years, range 18-42 years). The study also assessed intra-tester reliability of the technique. A good correlation was found between the findings of the clinical test for medio-lateral position and the MRI measure (r=0.611, p=0.002). All of the subjects found to have a laterally tilted patella on clinical examination had a lateral patella tilt defined by PTA of greater than 5 degrees . Those subjects with a PTA of less than 5 degrees on clinical examination were assessed as having no degree of patella tilt. The study undertaken shows that when undertaken by an experienced manual therapist positional assessment of the patella can have strong criterion validity and intra-tester reliability.

Adolescent↗
PubMed2001

Alterations in the patella after a high tibial or distal femoral osteotomy.

Knee osteotomies realign the knee in an attempt to better distribute forces across the knee. The anatomic and physiologic function of the extensor mechanism, which includes the quadriceps tendon, patella, and patella ligament, may be altered during this procedure. An understanding of these changes is important especially when additional surgery becomes necessary, such as a conversion to a total knee arthroplasty. The current authors discuss patella mechanics and changes in the patella associated with osteotomies about the knee and the influence on normal patella biomechanics. Although patella changes are uncommon after a distal femoral osteotomy, poor total knee arthroplasty outcomes after a high tibial osteotomy attributable to patella alterations exist. Surgical technique during the primary high tibial osteotomy and the conversion to the total knee arthroplasty can reliably improve the final outcome. Rigid internal fixation with early knee mobilization after high tibial osteotomy reduces the incidence of patella baja and improves total knee arthroplasty outcome after a high tibial osteotomy, whereas while patella changes after a distal femoral osteotomy are minimal and largely ignored.

Biomechanical Phenomena↗
PubMed2004

Long-term changes of the nonresurfaced patella after total knee arthroplasty.

BACKGROUND: The most common complications of total knee arthroplasty involve the patellofemoral joint. However, the long-term fate of the nonresurfaced patella after total knee arthroplasty has seldom been reported. The purpose of this study was to evaluate the long-term changes of the nonresurfaced patella after total knee arthroplasty. METHODS: We retrospectively evaluated the nonresurfaced patella in 227 knees (181 patients) at an average of 8.5 years after total knee arthroplasty. Functional results were correlated with radiographic changes, and risk factors leading to abnormal changes of the patella were analyzed. RESULTS: Preoperatively, 186 (82%) of the patellae tracked centrally, thirty-nine (17%) displaced or tilted laterally, and two (1%) subluxated laterally. At the time of the latest follow-up, 133 (59%) of the patellae still tracked centrally with preservation of the cartilage thickness, fifteen (7%) showed early lateral tilt, sixty-eight (30%) had progressive loss of lateral cartilage thickness with lateral tilt and/or displacement, seven (3%) had progressed to lateral subluxation, and four (2%) tilted medially. An abnormal patellofemoral joint did not affect the knee and functional scores (p = 0.90 and 0.89, respectively). However, symptoms such as difficulty rising from a chair or reluctance to use the involved lower limb while climbing stairs were noted. Preoperative patellar maltracking was identified as the only risk factor leading to postoperative patellar abnormalities (relative risk, 2.7; 95% confidence interval, 2.21 to 3.30; p = 0.003). CONCLUSIONS: At the time of follow-up, at an average of 8.5 years, patellar tracking and the patellofemoral joint remained normal after approximately 60% of the total knee arthroplasties performed without resurfacing of the patella. Progressive degenerative changes of the nonresurfaced patella (mainly on the lateral facet) and patellar maltracking were the most common abnormal radiographic changes. Patients with preoperative patellar maltracking were at risk for the development of these changes and clinical symptoms. Resurfacing of the patella during total knee arthroplasty may benefit such patients.

Aged↗
PubMed1995

Olecranization of the patella.

Olecranization of the patella is a technique employed by some to maintain the normal anatomic relationship of the femorotibial articulation following posterior cruciate ligament (PCL) repairs and reconstructions. It involves temporarily placing a large diameter pin longitudinally through the patella and into the tibia. The patella thus becomes a bony shelf and, in theory, holds the tibia forward, protecting the knee from a posterior drawer force. This technique appears desirable in that it allows postoperative knee motion while theoretically affording protection to the PCL. Unfortunately, it is based on an erroneous concept that the spatial relationship of the patella and tibia remains constant throughout knee flexion. Negative experience at our institution with this technique prompted our investigation. Using lateral radiographs of 20 normal knees taken at four different positions of flexion, we studied the relative motion that occurs between the patella and tibia in the sagittal plane during knee flexion from 0 degrees to 90 degrees, and defined two separate arcs of patellar motion. The patellar tendon arc is a 30 degree arc through which the patella traverses relative to the tibia during knee flexion. The patellar arc is a 22 degree arc on which the patella flexes relative to itself during knee flexion. We also studied the effect that olecranization of the patella has on the PCL in six cadaver knees. Using a combination of direct tension measurement, radiographic measurement, and fluoroscopy, we found that olecranization of the patella not only fails to protect the PCL, but actually induces a detrimental posterior drawer force during knee flexion.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

[Roentgenographic and experimental studies of the patella alta].

Patella alta has so far been given attention with reference to the patellofemoral disorder. However, neither its morphological concept has been quite coherent yet nor its clinical significance has been fully understood. In order to clarify these points, the author made a roentgenographic investigation of patella alta and also conducted an experimental study. Defining as patella alta the condition in which the articular surface of the patella is higher than the patellar surface on the femur, the author evaluated the patella position by seizing, from the dynamic viewpoint, the positions of the articular surface of the patella to the patellar surface on the femur by serial roentgenography and their graphic representations. The results obtained revealed that in the patellofemoral osteoarthritis, compared with the normal, there was observed retarded descending of the patella into the femoral intercondylar notch at knee flexion. Moreover, on the rabbit knee whose patellar ligament was lengthened, descending condition of the patella similar to that observed for human patellofemoral osteoarthritis was created, thus leading to an experimental patellofemoral osteoarthritis. The above results suggested an of important role of patella alta in the pathogenesis of patellofemoral osteoarthritis.

Adolescent↗
PubMed1995

[Adjustable reconditioner for the treatment of patella fracture].

Patella fracture belongs to the articular fracture. The operative methods to fix the patella fracture are numerous and there is no unanimous view. In order to protect the reconditioned patella, usually it is necessary to fix externally for a period of time. Since 1989, the authors have treated 165 cases of patella fracture with self designed, adjustable reconditioner and have acquired satisfactory results both in its fixing effect and function recovery. There was no need to fix the patella externally and the patients could do functional training in early stage. According to the assessment of the postoperative function and the motion limits of the knee and rehabilitation of the fracture, the results of the treatment were: excellent in 148 cases and good in 17 cases. This article describes the fixing mechanism of the reconditioner. It consists of the left and right petals and a screw. According to different sizes of patella and various types of the fracture, the reconditioner could be adjusted to connect the fracture closely with the petals and a screw. The structure of the reconditioner is simple, the operation is easy to carry out. It is adjustable during the operation and holds the fracture firmly and secure. It is suitable for all kinds of patella fracture avoiding partial or total resection of the patella. The other facture of the reconditioner is that the fixed patella could bear traction force when bending the knee at 90 degrees, so the patient could walk and squat on the heels normally.

Adult↗
PubMed2002

A comparative study of bone to bone repair and bone to tendon healing in patella-patellar tendon complex in rabbits.

OBJECTIVES: To study the healing quality of bone to bone and bone to tendon repair in a patella-patellar tendon complex. DESIGN: In vivo animal experiment in 60 mature 32-week-old female rabbits. BACKGROUND: Injuries of patella-patellar tendon complex are not uncommon. However, no studies are available to compare the healing quality between bone to bone and bone to tendon surgical reconstructions used for repair of patella-patellar tendon complex. METHODS: A standard transverse osteotomy was performed at the distal one-third of patella of one hindlimb. Both patellar fragments were reattached for bone to bone group while the patellar tendon was reattached to the remaining patella after removing the distal one-third of patella for bone to tendon group. Patella-patellar tendon complex was harvested at 8, 12 and 24 weeks postoperatively for biomechanical and histological evaluations, with n=8 and n=2 at each healing time points in both groups. The contralateral knee served as a control. RESULTS: No significant differences in the failure loads were found between two groups. However, greater ultimate stress was found in bone to bone group as compared with bone to tendon group at week 8 and 24 (both P<0.05). On average, the ultimate stress of the bone to tendon and bone to bone group only reached 20.6(4.2)% and 28.6(6.7)% of the control values at week 24, respectively. The discrepancy between findings in failure load and failure stress might be explained by an overall larger cross-sectional area of the healing interface in bone to tendon group as compared with bone to bone group. Histology revealed that the bone to bone healing was via endochondral ossification at the healing interface. In bone to tendon group, extensive scar tissue was formed to overbridge the healing interface and remodeled with healing over time. The structural integration at the tendon and bony healing interface was poor and no typical intermitted fibrocartilage zone as seen in normal bone to tendon junction was formed. CONCLUSION: Failure load of bone to bone and bone to tendon healing interface did not differ during repair of patella-patellar tendon complex. However, the healing interface of bone to bone repair in terms of material properties as reflected by failure stress was superior to that of the bone to tendon healing. RELEVANCE: The findings of this experimental study may suggest that the anatomical reconstruction of patella-patellar tendon complex injury may be the primary concern in decision making for selecting either bone to bone or bone to tendon repair. However whenever possible, to initial fracture (bone-to-bone) fixation for ensuring better and predictable repair at the healing interface.

Analysis of Variance↗
PubMed1998

[Shift and tilt of the bony patella in total knee replacement].

Resurfacing the patella or not in total knee arthroplasty is generally still a quite controversial topic. In that context we felt a necessity to get more informations about the natural history of a non resurfaced patella in the prosthetic surrounding than only in comparison with a replaced patella. By the fact that we haven't been replacing patellae apart from special cases since up to five years, we have available a patient selection on which this question can be studied. Thirty primary total knee replacements with documented 2 year's follow up have been investigated by calculation of the radiological patellar shift and tilt relative to the natural groove on preoperative X-rays and to the prosthetic groove in the postoperative evolution. These results were matched with the range of motion obtained after two years and with persisting pain. Only mobile polyethylene inlays had been used. With regard to the patella no difference was found for one single complete tibial tray or two separately implanted unicompartimental tibial trays. As a rule an adaptation of the bony patellar contour to the prosthetic groove was observed with an increased density of the bony contact area with or without a fibrous interstitial layer. Based on their clinical follow up examination seven patients had to be adjointed to a "residual problem group", as they presented persisting pain (3) or a poor range of motion of 90/0/0 degree of flexion/extension or less. Only in this group we found cases with a postoperative shift over 5 mm (2) and a postoperative tilt over 15 degrees (3). Inside this group, also with a significant difference from the group without residual problems, there was furthermore a correlation between persisting pain and an important preoperative tilt and between a diminished range of motion and a considerable preoperative shift. It has to be pointed out that even the cases without long severe malposition before the arthroplasty but with unsatisfactory realignement referring to the patellar tilt (7 degrees-15 degrees) have been found pain free at the last follow up. One patient with a severe secondary increase of disalignment (16 mm/139 degrees) due to an aseptic tibial loosening represents a particular case. After corrective revision of the tibial implants this patient also got again a complete pain relief and a good range of motion without any surgical measure to the patella and inspite of an evident residual tilt. Thus we have to conclude that it is justified to take important pains with the realignment to obtain a residual patellar shift of less than 5 mm. Apart from usual operative steps during the implantation to favour a good patellar tracking, e.g. a high quadriceps release or a medially transposed refixation of the detached tibial tubercle can get necessary. On the other hand a residual tilt up to 15 degrees is well tolerated, as the unresurfaced patella presents an astonishing ability of adaptation to the prosthetic groove by remodelling of the bony contour and structure. Nevertheless in the included cases of severe preoperative malposition, in which we didn't replace the patella because of a good intraoperative bone quality, we had to put up with an increased incidence of late problems even with normalized patellar tracking. In such cases an extended indication to a patellar resurfacing may be considered.

Arthroplasty, Replacement, Knee↗
PubMed2001

[Problems in osteosynthesis of patella fractures with the AO tension belt and consequences for new implants. The XS nail].

The eccentric ventral AO tension belt system represents the standard therapy of fractures of the patella. This often leads to unsatisfying results. Relating to Klute and Meenen [10] and the results of our own retrospective study, expressed as a percentage, 5-34% (own results 12.4%) have extremely poor treatment outcome, 23-60% (39%) end in deficiencies of bending, and there are 51-79.5% (65.7%) with subjective complaints after patella osteosynthesis. The disadvantages due to the eccentric tension belt position and the impossibility of applying the tension belt directly to the bone surface are abolished with the development of the XS nail. Due to its central position, constant compression of the entire fracture surface is provided. This is valid for all tension-stressed fractures such as those of the patella and olecranon. In synthetic patellae [5] standardized stress testing with changing tension up to 500 Newton was carried out. The XS nail was compared with the AO tension belt osteosynthesis after osteotomy and osteosynthesis in synthetic patellae. The XS nail was superior to the tension belt for all tests and therefore can be applied to all types of fractures where tension stress exists. We repaired the first 15 patella fractures with the XS nail. In 13 of 15 cases, full load of the injured leg was possible (for stairs a plaster splint was used). The experimental patella tests and first clinical results with the XS nail osteosynthesis after patella fracture confirm the new type of osteosynthesis, and functional treatment with loading seems possible.

Adolescent↗
PubMed2005

Patella intraosseous blood flow disturbance during a medial or lateral arthrotomy in total knee arthroplasty: a laser Doppler flowmetry study.

Patella complications are recognized sequelae of total knee arthroplasty (TKA). Disruption of blood flow to the patella and adjacent soft tissues during surgery may contribute to reduced viability of the bone and patella ligament tissue. The effect on genicular blood flow to the medial and lateral patella was compared for a medial (MA) and lateral arthrotomy (LA) during TKA. Laser Doppler flowmetry was used to measure both baseline and postarthrotomy flow in vivo for 16 primary TKA patients. Flow in the lateral patella was reduced approximately 20% for both MA and LA. Conversely, the use of MA resulted in substantial reduction in flow to the medial patella (53%) compared to the lateral approach (27%). A large standard deviation of scores was evident in all cases. Although there was a tendency for LA to disturb the patellar blood flow less, the difference was not significant. It was concluded that neither approach is superior regarding the blood flow preservation to the patella. Hence, a lateral approach might only have an advantage in knee joints that are likely to need a lateral release in combination with an MA-e.g., a valgus deformity or preoperative patella maltracking.

Aged↗
PubMed2006

Hemilaterally symptomatic bipartite patella associated with bone erosions arising from a gouty tophus: a case report.

Symptomatic bipartite patella in adults is rare. We have treated an unusual case of a bipartite patella in an adult, which became symptomatic in association with cystic degeneration localized to the patella and a gouty tophus. Although the patient had bilateral bipartite patellae, multiplanar reformation with computed tomography (CT-MPR) clearly demonstrated that the bipartite portion of the patella was malaligned at the junction of the accessory bone and patella in the symptomatic knee. Bone erosions were present both in the bipartite fragment and adjacent portion of the patella. After surgical excision of the bipartite fragment, the patient's symptoms have improved. This case illustrates that cyst formation associated with inflammatory arthritis may be a rare cause for a bipartite patella in an adult to become symptomatic.

Adult↗
PubMed1997

Cosegregation of open-angle glaucoma and the nail-patella syndrome.

PURPOSE: To evaluate two families ascertained only for the presence of glaucoma in which both nail-patella syndrome and glaucoma occur in several generations and to determine whether the two diseases are genetically related. METHODS: Ophthalmologic examinations and orthopedic examinations were performed. DNA samples from family members were screened with a microsatellite repeat marker at the argininosuccinate synthetase (ASS) locus at 9q34, and linkage analysis was performed. RESULTS: Six patients with open-angle glaucoma were found among 13 patients with nail-patella syndrome in family UM:47. Seven patients with glaucoma were found among 11 patients with nail-patella syndrome in family UM:65. In both families, all individuals with glaucoma also had nail-patella syndrome. Two-point linkage analysis resulted in a lod score of 2.98 at a recombination fraction of 0.00 for open-angle glaucoma and nail-patella syndrome. CONCLUSIONS: Linkage results presented here provide strong evidence that the orthopedic and nail anomalies in these two families result from the same nail-patella syndrome locus that has been previously linked to markers at 9q34. These data provide indirect evidence for a possible glaucoma locus at 9q34 and do not allow us to distinguish whether the glaucoma is the result of the nail-patella syndrome mutation or whether there is a separate locus responsible for glaucoma in these families. These studies suggest a need for ophthalmologic examination of individuals with nail-patella syndrome.

Aged↗
PubMed1997

Medialization of the patella in total knee arthroplasty.

Patellar complications of total knee arthroplasty remain the most common cause of pain and reoperation. Laboratory studies have suggested that medialization of the patella will improve tracking of the patella on the trochlea of the femoral component. The purpose of this study was to determine if clinical medialization of the patellar component on the patellar bone would improve tracking of the patella as demonstrated radiographically. Sixty-two knees were randomized so that 31 knees had a centrally placed patellar component and 31 had the patellar component placed on the medial two thirds of the patellar bone. There was no difference between the two groups with respect to either clinical or radiographic results in the first year after surgery. There was no improvement compared with previous reports in the incidence of tilt and displacement. The one improvement was a reduction in the incidence of lateral release. Thus, consequences of lateral release such as postoperative morbidity, avascular necrosis of the patella, and stress fracture of the patella can be avoided. It is recommended that the patellar component be placed on the medial two thirds of the patella to reduce the occurrence of lateral release. Tracking of the patella during surgery can be assessed using a single suture placed at the superior pole of the patella, and this technique in combination with the no-thumbs test provides an additional means of evaluation for patellar tracking.

Adult↗
PubMedDate not supplied

The incidence and outcome of patella fractures after anterior cruciate ligament reconstruction.

PURPOSE: The study was performed to determine the incidence and eventual outcome of patella fractures after anterior cruciate ligament (ACL) reconstructions using bone-patella tendon-bone autograft. TYPE OF STUDY: Retrospective review. METHODS: Between 1989 to 1999, 618 consecutive primary, single-incision bone-patella tendon-bone autograft ACL reconstructive procedures were performed by 3 surgeons at our institution. Of this group, 8 (1.3%) had postoperative patella fracture of the donor knee. The charts of these patients were retrospectively reviewed, and patients were followed with physical examination and outcome questionnaires. RESULTS: The patella fractures occurred at a mean of 57 days after the ACL reconstruction (range, 24-121 days). Five patients sustained indirect trauma, whereas 3 experienced direct trauma. Three patients had nondisplaced transverse fractures treated nonoperatively. Five patients had displaced fractures (3 transverse and 2 Y-shaped) requiring surgical intervention. All 8 patients have full flexion when compared with their opposite knee. Two patients did not regain 5 degrees of hyperextension but were not symptomatic. The mean length of follow-up for the questionnaire was 4 years (range, 1.5 to 6.5 years). The mean score on the Lysholm knee questionnaire was 89.6 (range, 77-98). The mean Single Assessment Numeric Evaluation score was 85.8 (range, 50-100). CONCLUSIONS: Most cases of postoperative patella fractures, in our experience, have caused minor changes postoperatively and no differences in the outcome of these patients. Seventy-five percent of our patients had excellent or good Lysholm scores. This study confirms previous reports in the literature that observed minimal residual sequelae from postoperative patella fractures after ACL reconstruction with bone-patella tendon-bone autograft.

Adult↗
PubMed2002

The inter-tester reliability of a clinical measurement used to determine the medial-lateral orientation of the patella.

An important aspect of the patellar taping technique, a common treatment for patellofemoral pain is the assessment of patellar position. The inter-tester reliability of the assessment method has been regarded as poor, as has the validity (Powers et al. 1999). The purpose of the study was to determine inter-tester reliability of a group of trained manual physiotherapists. This was achieved using a clinical measurement to assess the medial/lateral orientation of the patella and compare these findings against a known criterion valid measurement of patella position. Twenty experienced manual physiotherapists evaluated medial/lateral orientation of the patella. The findings of the clinical assessment were then compared to the position of the patella as determined through magnetic resonance imaging (MRI). The MRI and the clinical assessment were carried out on the right knee of a single subject, who was supine with the knee in 20 degree flexion with the quadriceps relaxed. Both measures found the patella to be laterally displaced. Using the clinical method the mean difference between medial and lateral measurements was 6.4 mm (+/- 3.9 mm). The MRI measure of lateral patella displacement found the patella to be displaced 5 mm laterally. The inter-tester reliability of the clinical test showed good agreement, r = 0.91 for the medial measure and r = 0.94 for the lateral measure. The agreement between the clinical and MRI measures was (r = 0.9) which was also a significant agreement. This study appears to demonstrate that experienced manual physiotherapists can reliably measure relative patella medial/lateral position.

Arthralgia↗
PubMed1997

A comparison between the patella and the calcaneus using ultrasound velocity and attenuation as predictors of bone mineral density.

The bone mineral density (BMD), ultrasound velocity (UV) and attenuation were examined in sixteen matched sets of human patellae and calcanei. For the sixteen calcanei, BMD was strongly correlated with all ultrasound parameters. Calcaneal UV appeared to be inferior to attenuation in the ability to predict BMD. For the sixteen patellae, the average UV was found to be greater in the superior/inferior direction than in the anterior/posterior and medial/lateral directions. It was found that patella BMD was significantly correlated with each of three directional ultrasound velocities. The relationship between BMD and ultrasound attenuation parameters was not significant in the patella. A comparative study of the two different bone sets demonstrated that the BMDs of the patella and calcaneus were significantly correlated with each other. Ultrasound velocity of calcaneus, measured in the medial/lateral direction, was not significantly associated with any of three directional ultrasound velocities in the patella. Similarly, ultrasound attenuation parameters of calcaneus were not significantly correlated with those of patella. The present study also demonstrated evidence that when predicting BMDs at their respective sites using ultrasound, the calcaneus appeared to be superior to the patella.

Aged↗
PubMed1995

The effect of knee flexion and quadriceps contraction on the axial view of the patella.

Axial views of the patella are standard in the investigation of anterior knee symptoms, and many investigators use congruence angles and patellar tilt in determining the diagnosis and appropriate treatment. A variety of different methods are used to obtain axial radiographs of the patella, but they are static representations of a dynamic phenomenon. The effect of quadriceps contraction on these indices has not been well defined. The purpose of this study was to compare the 30 degree axial view of the patella with the 45 degree axial view of the patella and to study the effect of quadriceps contraction on the 30 degree axial radiograph of the patella. Forty knees with normal patellofemoral joints and 20 knees with patellar subluxation were radiographed using 30 degree axial views of the patella with the quadriceps relaxed and contracted and with 45 degree axial views with the quadriceps relaxed. There was no significant difference in the sulcus or congruence angles between the 30 and 45 degree axial view in either the control or the patellar subluxation group. Contraction of the quadriceps did not cause a significant or consistent alteration in the congruence angles in either group. With quadriceps contraction, 55% of patients will centralize the patella, whereas 40% will actually increase lateral tracking or subluxation. In conclusion, the 30 degree axial view of the patella is equivalent to the 45 degree axial view in the assessment of patellar subluxation. Quadriceps contraction does not alter the congruence angles obtained in these axial views in a significant or consistent manner.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1997

Intra-articular dislocation of the patella: case report and literature review.

PURPOSE: To inform physicians treating sport injuries of a rare and unique form of patella dislocation, the horizontal intra-articular dislocation of the patella. CASE SUMMARY: A young male sustained a direct blow to the upper pole of the patella and came into the emergency room with a knee locked at 75 degrees of flexion. He had an irreducible dislocation of the patella in which the patella was displaced inferiorly, rotated 90 degrees, and locked into the intercondylar notch of the femur. DISCUSSION: This injury occurs most often in young men and usually requires open reduction. Literature review indicates patients presenting a knee near full extension have a better chance for successful closed reduction, possibly because of a lesser degree of patella entrapment in the intercondylar notch. RELEVANCE: Most physicians are unaware of this rare type of patella dislocation. It can, however, be recognized by its typical mechanism of injury and clinical features. Unlike the common lateral patella dislocation, on-site reduction is not possible. This injury requires closed and often open reduction under general anesthesia.

Adult↗