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P Lobenhoffer

Publications and source records attributed to P Lobenhoffer.

At least 19 recordsLinked to original sources
PubMed2006

[Arthroscopic capsular release in the management of refractory adhesive capsulitis. Technique and results].

Idiopathic adhesive capsulitis can severely restrict the comfort and function of the entire extremity, often resulting in prolonged, substantial disability. Some studies have demonstrated long-term residual pain and limitation of motion in most patients after conservative treatment such as physical therapy or corticoid injection. Closed manipulation is associated with severe complications. We report the technique and results of arthroscopic capsular release as an effective and safe alternative for the management of refractory adhesive capsulitis. We operated 23 patients between June 2003 and November 2004 who suffered from a loss of glenohumeral motion in all planes arthroscopically. Ten of the patients were evaluated after a mean follow-up of 6 months. We found significant pain relief a few days after surgery in every patient. Furthermore, we found improvements in the range of motion in all planes. Abduction improved from preoperative 50 degrees to postoperative 120 degrees , flexion from 55 degrees to 120 degrees, external rotation from 10 degrees to 60 degrees and internal rotation from 20 degrees to 65 degrees. The average Constant Score improved from preoperative 32 to postoperative 81 points. Arthroscopic capsular release is an effective and safe technique for the management of refractory adhesive capsulitis, avoiding prolonged disability.

Adult↗
PubMed2006

[Arthrolysis for chronic flexion deficits of the knee. An overview of indications and techniques of vastus intermedius muscle resection, transposition of the tibial tuberosity and z-plasty of the patellar tendon].

AIM AND METHOD: Limitations to the range of motion of the knee reduce knee function and life quality. Flexion deficits inhibit using stairs and shoe closure, and may cause social deprivation. We present a pathophysiological concept of arthrolysis of the knee for flexion deficit. Our concept divides into intra- and extra-articular factors involving knee stiffness. Extra-articular problems can be located proximally in the quadriceps mechanism and distally in the patellar tendon. RESULTS: The main proximal factor is fibrosis of the vastus intermedius muscle (MVI) which is treated by MVI-resection; the main distal factor is shortening of the patellar tendon which is treated by z-plasty of the this tendon or transposition of the tibial tuberosity. Intra-articular factors are adhesions and fat pad fibrosis. These conditions can be treated by arthroscopic or limited open arthrolysis and eventually z-plasty of the retinacula. CONCLUSION: A strict postoperative protocol is obligatory for pain control and physiotherapy. In 19 cases treated with this algorithm there was a mean flexion gain of 26 degrees. The AOSSM subjective outcome score was excellent in ten and good in seven cases after a mean follow-up of 8.2 months. This treatment protocol allows improvement in flexion, even in difficult revision cases.

Ankylosis↗
PubMed2006

Joint position awareness and sports activity after capsulolabral reconstruction in the overhead athlete.

A total of 24 overhead athletes with posttraumatic, chronic anterior shoulder instability underwent surgery. Twenty-two patients were examined after an average follow-up of 2.8 +/- 0.7 years. On average, a Constant-Score and Constant-Murley-Score of 93.7 +/- 5.3 points and an ASES-Score of 95.0 +/- 5.1 points were achieved. The redislocation rate was 9 %. The study demonstrated, that despite the good clinical results, only 12 out of 22 (55 %) of patients were able to return to their previous sports activity level. This relevant problem is in agreement with other similar studies [ ], so it was further addressed by determination of joint position awareness (JPA) and electromyographic muscle activity. Postoperatively, a persisting deficit of JPA, as well as an altered EMG pattern, was found with a significant reduction in activity of the deltoideus muscle on the operated side. The analysis of the data of each patient showed that there was a significant relation between the restitution of JPA and ability to return to the previous sports activity level. In contrast, the relation between EMG pattern and full recovery to completely unrestricted shoulder function was not significant. The anterior capsulolabral reconstruction enables a reliable restoration of shoulder stability and a low rate of complications. The problem that a relatively high percentage of overhead athletes can not return to their previous performance level is based on an impaired joint position awareness.

Adolescent↗
PubMed2005

Primary stability of four different implants for opening wedge high tibial osteotomy.

Since a significant number of implant failures have been reported in association with the procedure of open wedge valgus high tibial osteotomy, the initial biomechanical stability of different fixation devices was investigated in this study. Fifteen third generation Sawbones composite tibiae were used as a model. Four different plates were tested: a short spacer plate (OWO) (n = 4), a short spacer plate with multi-directional locking bolts (MSO) (n = 5), a prototype version of a long spacer plate with multi-directional locking bolts (MSOnew) (n = 2), and a long medial tibia plate fixator with locking bolts (MPF) (n = 4). All opening wedge osteotomies were performed by the same surgeon (PL) in a standardized fashion. Axial compression of the tibiae was performed using a materials testing machine under standardized alignment of the loading axis. Single load to failure tests as well as load-controlled cyclical failure tests were performed. The required force and cycles to failure were recorded. Osteotomy gap motion was measured using linear displacement transducers. Residual stability after failure of the opposite lateral cortex was analysed. Failure occurred at the lateral cortex bone-bride in all tested implants. The rigid long plate fixator (MPF) resisted the greatest amount of force (2,881 N) in the single load to failure tests. In the cyclical load-to-failure tests, the constructs with MPF resisted more than twice the amount of loading cycles when compared to the short spacer plates. The osteotomy gap motion was smallest in the MPF, with a reduction of the displacements of up to 65, 66 and 88%, when compared to OWO, MSO and MSOnew, respectively. The highest residual stability after failure of the lateral cortex was observed in MPF as well. The results suggest that the implant design strongly influences the primary stability of medial opening wedge tibial osteotomy. A rigid long plate fixator with angle-stable locking bolts yields the best results.

Bone Plates↗
PubMed2005

[Patella fractures].

Patella fractures are relatively uncommon, accounting for approximately 0.5% to 1.5% of all skeletal injuries. The most common mechanism for this injury is direct fall onto the knee, and transverse fracture is the most common type. The aims of operative treatment are accurate reduction and rigid fixation. Stable fracture types without or with minimal dislocation can be treated nonoperatively. Dislocation of more than 2 mm and comminuted fractures are indications for operative treatment. Tension band wiring, interfragmentary screw fixation, and the combination of cerclage wiring and screw fixation are used for internal fixation of these fractures. When accurate reduction and reconstruction of the retropatellar joint surface cannot be achieved in multi-fragmentary fractures, partial or total patellectomy should be considered. Since it always results in loss of quadriceps muscle power, the decision for this procedure should be made cautiously.

Adult↗
PubMed2005

[Sensorimotor deficit after capsulolabral reconstruction in chronic instability of the shoulder. A clinical experimental study].

The anterior capsulolabral reconstruction technique described by Jobe is a modified Bankart repair. The capsular shift is performed in a horizontal direction via a subscapularis split approach avoiding any incision of the muscle. Of 43 patients with posttraumatic anterior shoulder instability treated by anterior capsulolabral reconstruction, 35 were examined after 3.7+/-1.4 years, and of these, 29 (82.9%) had no pain; the external rotation deficit was 4.1+/-2.9 degrees . The average Constant-Murley score was 92.4+/-7.1 and the average ASES score was 93.3+/-8.4. The reluxation rate was 7.7%. This technique was shown to provide good clinical results, but only 69% of the patients were able to return to their prior sporting activity level. This particular problem was addressed by investigating the joint proprioception and the activity of the periarticular muscles. The results confirmed a persistent deficit of proprioception as well as a pathologic EMG pattern after anterior capsulolabral reconstruction, which may explain the problem of incomplete restoration of the function of the shoulder joint.

Adolescent↗
PubMed2005

[A simplified technique for repair of quadriceps tendon rupture by transpatellar PDS-cord].

Quadriceps tendon ruptures are relatively unusual injuries caused by direct or more frequently indirect trauma. Since complete ruptures lead to loss of active extension of the knee joint, operative treatment is usually indicated. Several techniques are described in the literature. However, relatively little is known about the functional outcome after operative treatment of acute quadriceps tendon ruptures. We present a new operative technique using a 1.3-mm PDS cord passed through a transverse drill hole in the proximal pole of the patella. We operated ten consecutive cases of complete quadriceps tendon ruptures with the technique described between January 2000 and June 2003. Eight of ten patients were evaluated after a mean follow-up time of 38 months by physical examination, IKDC Subjective score, Lysholm and Tegner score as well as an isokinetic test of the quadriceps strength. No complications were noted in this period. The average postoperative scores were 87 (IKDC), 98 (Lysholm), and 4.5 (Tegner). Isokinetic testing showed an average of 25% quadriceps strength deficit. The operative treatment of complete quadriceps tendon ruptures using a PDS cord through a drill hole in the patella is a safe and effective technique permitting functional postoperative treatment.

Adolescent↗
PubMed2005

[Capacity for sport and the sensorimotor system after stabilization of the shoulder in overhead athletes].

The anterior capsulolaboral reconstruction according to Jobe is a modification of the Bankart operation, performing the capsular shift via a subscapularis-split approach avoiding any incision into the musculature. A total of 24 overhead athletes with posttraumatic, chronic anterior shoulder instability underwent surgery. Twenty-two patients were examined after an average follow-up of 2.8 +/- 0.7 years. On average, a Constant-Murley-Score of 93.7 +/- 5.3 points and an ASES-Score of 95.0 +/- 5.1 points were achieved. The relaxation rate was 9 %. The study demonstrated, that despite the good clinical results, only 12 out of 22 (55 %) of patients were able to return to their previous sports activity level. This relevant problem is in agreement with other similar studies so that it was further addressed by determination of proprioception and electromyographic muscle activity. Postoperatively, a persisting proprioceptive deficit as well as an altered EMG pattern was found with a significant reduction in activity of the deltoideus muscle on the operated side. The analysis of the data of each patient showed that there was a significant relation between the restitution of proprioception and ability to return to the previous sports activity level. In contrast, the relation between EMG pattern and full recovery to completely unrestricted shoulder function was not significant.

Adolescent↗
PubMed2004

Effect of high tibial flexion osteotomy on cartilage pressure and joint kinematics: a biomechanical study in human cadaveric knees. Winner of the AGA-DonJoy Award 2004.

INTRODUCTION: Valgus high tibial osteotomy is an established treatment for unicompartmental varus osteoarthritis. However, only little is known about the effect of osteotomy in the sagittal plane on biomechanical parameters such as cartilage pressure and joint kinematics. This study investigated the effects of high tibial flexion osteotomy in a human cadaver model. MATERIALS AND METHODS: Seven fresh human cadaveric knees underwent an opening wedge osteotomy of the proximal tibia in the sagittal plane. The osteotomy was opened anteriorly, and the tibial slope of the specimen was increased gradually. An isokinetic flexion-extension motion was simulated in a kinematic knee simulator. The contact pressure and topographic pressure distribution in the medial joint space was recorded using an electronic pressure-sensitive film. Simultaneously the motion of the tibial plateau was analyzed three-dimensionally by an ultrasonic tracking system. The traction force to the quadriceps tendon which was applied by the simulator for extension of the joint was continuously measured. The experiments were carried out with intact ligaments and then after successively cutting the posterior and anterior cruciate ligaments. RESULTS: The results demonstrate that tibial flexion osteotomy leads to a significant alteration in pressure distribution on the tibial plateau. The tibiofemoral contact area and contact pressure was shifted anteriorly, which led to decompression of the posterior half of the plateau. Moreover, the increase in the slope resulted in a significant anterior and superior translation of the tibial plateau with respect to the femoral condyles. Posterior subluxation of the tibial head after cutting the posterior cruciate ligament was completely neutralized by the osteotomy. The increase in slope resulted in a significant higher quadriceps strength which was necessary for full knee extension. CONCLUSIONS: We conclude from these results that changes in tibial slope have a strong effect on cartilage pressure and kinematics of the knee. Therapeutically a flexion osteotomy may be used for decompression of the degenerated cartilage in the posterior part of the plateau, for example, after arthroscopic partial posterior meniscectomy. If a valgus osteotomy is combined with a flexion component of the proximal tibia, complex knee pathologies consisting of posteromedial cartilage damage and posterior and posterolateral instability can be addressed in one procedure, which facilitates a quicker rehabilitation of these patients.

Aged↗
PubMed2004

[Results of the provision of unstable proximal humeral fractures in geriatric patients with a new angle stabilizing antegrade nail system].

Treating unstable proximal humeral fractures in elderly patients with osteoporosis and limited compliance is still demanding for trauma surgeons. The failure rate of operative treatment is high. We studied the use of a new antegrade intramedullary humeral nail with special locking bolts for head fixation. The first 41 procedures in 39 patients with a mean age of 81 years (61-102) were analyzed. Half of the patients were mentally deranged. There were 16 two-part, 22 three-part, and 3 four-part fractures of the humeral head treated. After closed or partial open reduction, antegrade nailing was performed via a delta split and limited incision of the rotator cuff. Greater and lesser tuberosities were fixed with screws through threaded holes of the proximal nail leading to high stability. Early functional active treatment was performed avoiding maximal rotation. Follow-up was 13 months (7-21 months). Clinical examination was performed in 32 cases. Four patients were questioned by phone. Three patients died (mean age: 92 years) before follow-up. The mean Constant score was 57+/-12. The mean age-related and side-related Constant scores were 86+/-17% and 90+/-7%. All fractures healed. Activities of daily life were possible in every case. There was only one loss of reduction after a fall out of bed. After hemiarthroplasty the patient was excluded from the study. One shaft fissure occurred during distal interlocking and healed uneventfully. Because of stable fixation, rehabilitation without immobilization was possible and led to good functional results. In comparison to common implants, the new antegrade intramedullary nail allowed a stable osteosynthesis in unstable proximal humeral fractures in old and very old patients with limited compliance without the usual implant-related complications.

Aged↗
PubMed2004

[The minimally-invasive screw osteosynthesis of the medial femoral neck fracture in the very old. A prospective clinical study].

Increasing life expectancy has led to an increase of medial femoral neck fractures. Treatment by hip arthroplasty is a major surgical procedure for geriatric patients and imposes high healthcare costs. Manninger developed a cannulated screw system which allows a joint-sparing, less invasive, and stable internal fixation for the management of intracapsular femoral neck fractures. In a prospective study from January 1998 to August 2002, 63 patients older than 70 years with Garden type I to III fractures were treated by closed reduction and internal fixation with two Manninger screws on a traction table within the first 6 h after trauma. Mean time of follow-up was 21.5+/-16 months. Of the patients examined, 88.5% regained their preoperative stage of mobility. Two patients needed secondary hip arthroplasty. Due to low complication and failure rates and less medical expenses compared to treatment by hemiprosthesis the joint-sparing, less invasive internal fixation with two cannulated Manninger screws presents a safe and cost-efficient surgical technique for geriatric patients.

Aged↗
PubMed2004

[Endoprostheses of the knee joint].

Due to the advances in prosthesis design and standardisation of implant techniques, the maintenance of implants in arthroplasty of the knee joint has enormously increased during the past few years. Various arthroplastic designs enable an adjustment towards the patient's individual indiction and anatomy. For one-compartmental arthrosis, monocondylous prosthesis can be implanted using microinvasive operation techniques. Prerequisite for mere joint resurfacing is an intact lateral ligament apparatus, whereas the the symmetrical ligament balancing is essential for long-term analgesia, joint stability and good flexion. Aseptic loosening, discreet infections, instabilities and patellar problems are common reasons for painful knee arthroplastics.

Arthroplasty, Replacement, Knee↗
PubMed2004

[Arthroscopic meniscus surgery].

Surgery on the meniscus of the knee joint is one of the most frequently performed operations. The arthroscopic technique currently represents the general treatment standard and except in a few cases has completely superseded the open approach. Arthroscopy facilitates precise diagnosis and classification of all forms of meniscus lesions. In many cases even today partial resection on irreparably damaged meniscus tissue cannot be avoided. The goal is to preserve as much healthy meniscus tissue as possible. Types of tears amenable to reconstruction always require arthroscopic refixation. Various techniques are possible which have different advantages and disadvantages depending on the site of the lesion. In comparison to conventional techniques, in many cases modern implants and instruments make meniscus reconstruction easier entailing less morbidity. Substitution of lost meniscus tissue is possible with allograft transplantation; good results are possible especially on the lateral meniscus. A novel alternative is arthroscopic implantation of a biodegradable collagen matrix, which replaces partial defects on the medial meniscus. Long-term results of this treatment form must be awaited.

Arthroplasty, Replacement, Knee↗
PubMed2004

[Imaging and preoperative planning of osteotomy of tibial head osteotomy].

Valgus-producing osteotomy of the proximal tibia is a well-established treatment for medial femorotibial osteoarthritis in the varus knee. The ideal patient is active, under 55 years of age, has a stable varus deformity of less than 10 degrees, a good bone stock, and an osteoarthritis stage that is restricted to the medial compartment of the knee. Coventry reported a failure rate in proximal tibial osteotomy to be significantly higher when the postoperative alignment was less than 8 degrees of anatomical valgus. Hernigou noted better clinical long-term results in cases with a precise correction of malalignment. There are different preoperative planning methods varying between simple estimates of correction angles and specific radiographic planning tools. The reproducibility of operative outcome with regard to a predictable anatomic alignment and functional recovery must have high priority. This chapter deals with different preoperative planning methods to improve the reliability of surgical results after tibial osteotomy.

Adult↗
PubMed2004

[Open valgus alignment osteotomy of the proximal tibia with fixation by medial plate fixator].

High tibial osteotomy (HTO) is an established technique for the treatment of the symptomatic varus malaligned knee. Correction is usually achieved by closed wedge osteotomy from a lateral exposure. This procedure has a certain risk potential regarding peroneal nerve injuries, instability of the osteotomy and secondary loss of correction. We present four technical modifications of HTO which improve safety and reproducibility of this operation. 1) Open wedge osteotomy from a medial exposure avoids lateral muscle detachment, dissection of the peroneal nerve, proximal fibula osteotomy and leg shortening. Only one osteotomy needs to be performed and the correction can be adapted intraoperatively. 2) A biplanar osteotomy provides improved rotational stability of the osteotomy and creates an anterior buttress against sagittal tilting. 3) An incomplete osteotomy with plastic deformation of the intact lateral bone bridge avoids fractures of the lateral cortex and instabilities and promotes bone healing. 4) Rigid fixation with a medial plate-fixator (Tomofix) allows for early mobilisation and avoids loss-of-correction. 262 patients were consecutively operated using the described modified technique until now. No loss-of-correction occurred in this group, two patients with delayed healing received secondary cancellous bone grafts.

Adult↗
PubMed2003

[The direct, dorsal approach to the treatment of unstable tibial posteromedial fracture-dislocations].

The surgical treatment of highly unstable tibial posteromedial fracture-dislocations (medial split fracture,Moore type I) is demanding and may cause significant problems. The anterior and the posteromedial approach require detachment of the medial capsuloligamental structures or arthrotomy of the knee joint. Neither of these operative techniques allow the optimal posterior positioning of the buttress plate in order to prevent caudal dislocation of the fragment during knee flexion. The published posterior approaches to the proximal tibia allow appropriate positioning of the anti-glide plate. However, these surgical exposures involve transsection of the semi-membranous and popliteal muscles as well as the partial dissection of the medial gastrocnemius muscle. We present a direct posterior approach and an operative treatment of medial split fractures with open reduction and internal fixation in a prone position. This position simplifies the reduction of the posteromedial fragment by hyperextension and axial traction, as well as osteosynthesis with lag screws and the placement of the buttress plate (radial T-plate). The surgical exposure requires minimal soft tissue dissection. The inferior spike of the fragment can be visualized by partial subperiosteal detachment the popliteal muscle,whereas the medial gastrocnemius muscle and the semi-membranous muscle are preserved. Due to the voluminous subcutaneous tissue in the posteromedial tibial aspect, the closure of the skin incision over the medial gastrocnemius muscle can be performed without difficulty. Three cases of tibial posteromedial fracture-dislocation were treated by the direct posterior approach in a prone position in January and February 2002. The present report shows that the direct posterior surgical technique allows optimal exposure, reduction and internal fixation of medial split fractures of the tibial plateau with minimal trauma.

Adult↗