Biomedical subjects

Bradley M Lamm

Publications and source records attributed to Bradley M Lamm.

14 recordsLinked to original sources

PubMed2006

External fixation for the foot and ankle in children.

During the last decade, external fixation for the pediatric foot and ankle has evolved as a result of advances in technology (eg, Taylor spatial frame, hydroxyapatite-coated external fixator pins) and preoperative deformity planning. Although complications are common, most are minor and can be addressed nonoperatively while treatment continues. This article reviews the indications and applications of external fixation for soft tissue contractures, idiopathic and teratologic clubfoot, osteotomies, metatarsal lengthening, tibial lengthening, and foot and ankle trauma.

Bone Lengthening↗

PubMed2006

Treatment of malunion and nonunion at the site of an ankle fusion with the Ilizarov apparatus. Surgical technique.

BACKGROUND: Malunion and nonunion of an ankle fusion site are associated with pain, osteomyelitis, limblength discrepancy, and deformity. The Ilizarov reconstruction has been used to treat these challenging problems. METHODS: We reviewed the results in twenty-one ankles that had undergone a revision of a failed fusion, with simultaneous treatment of coexisting pathologic conditions, with use of the Ilizarov technique. Eight patients had undergone ankle fusion only, eleven had undergone ankle and subtalar fusion, and two had undergone pantalar fusion. Eighteen patients with an average limb-length discrepancy of 4 cm underwent limb lengthening simultaneously with the revision surgery. The average patient age was forty years. Indications for treatment were malunion (eleven patients), aseptic nonunion (eight patients), and infected nonunion (two patients). Clinical, subjective, objective, gait, and radiographic analyses were performed after an average duration of follow-up of 83.4 months. RESULTS: Solid union was achieved in all ankles. The functional result was excellent for fifteen patients, good for three, fair for two, and poor for one. The bone result was excellent for ten ankles, good for nine, fair for one, and poor for one. All eighteen patients who underwent gait analysis had a heel-to-toe progression gait, and twelve achieved normal walking velocity with their shoes on. A plantigrade foot was achieved in each case, and only two patients had >5 degrees of residual deformity. During the Ilizarov treatment, forty-one minor complications (treated conservatively) and twenty major complications (treated surgically) occurred. After removal of the circular frame, seven other complications, which required four additional operations, occurred. CONCLUSIONS: In patients with a failed ankle fusion, infection, limb-length discrepancy, and foot deformity can be addressed simultaneously with use of the Ilizarov apparatus to achieve a solid union and a plantigrade foot, usually with a clinically satisfactory result.

Ankle Joint↗

PubMed2005

Ankle joint distraction.

Ankle joint distraction is a viable alternative to ankle arthrodesis or ankle replacement. A congruent, painful, mobile, and arthritic ankle joint that is treated with this technique can achieve good to excellent results. Attention to the principles (anterior osteophyte resection, equinus contracture release, and ankle joint realignment procedures) is as important for a successful outcome as the accurate application of the hinged ankle joint distraction technique itself.

Animals↗

PubMed2004

Deformity correction planning for hindfoot, ankle, and lower limb.

Many patients with foot and ankle deformities have concurrent deformities (osseous and soft tissue), with or without limb length discrepancies. Lower extremity deformities and limb length discrepancies typically result from trauma, congenital abnormality, avascular necrosis, previous surgery, nonunion, and malunion. Limb deformity correction requires extensive surgical experience because many considerations and factors apply to realignment. The considerations and factors regarding realignment are highlighted throughout this article.

Ankle Joint↗

PubMed2004

Correction of the cavus foot using external fixation.

Cavus deformity is of soft tissue, bony, or combined origin and is either static or progressive. The treatment algorithm depends on these factors. Bony deformities are treated by acute osteotomy or gradual distraction osteotomies, whereas soft tissue contractures are treated by soft tissue releases or distraction. External fixation is a powerful tool to obtain correction of the cavus deformity. It must be supplemented with soft tissue balancing procedures, such as tendon transfer and orthotic management, to maintain the correction in progressive cavus deformities.

Algorithms↗

PubMedDate not supplied

Peroneal tendon tears: a retrospective review.

Tears of the peroneal tendons are not uncommon but remain an underappreciated source of chronic lateral ankle pain. The purpose of this study was to identify the typical patient profile and nature of the injury, to analyze the course of treatment, and to determine the prevalence of complications seen with surgical repair. Forty patients with chronic pain over the peroneal tendons from the Foot and Ankle Institute at the Western Pennsylvania Hospital underwent peroneal tendon repair. During a 3-year period, a retrospective review was performed by evaluating medical records, surgical reports, and radiographs. The average patient age was 42 years (range, 13 to 64 years). The most common cause was an ankle sprain or other traumatic injury (58%). Peroneus brevis tears (35 patients; 88%), peroneus longus tears (5 patients; 13%), combined peroneus brevis and longus tears (15 patients; 37%), low-lying peroneus muscle belly (13 patients; 33%), lateral ankle ligamentous disruptions (13 patients; 33%), and peroneal subluxation (8 patients; 20%) were identified during surgery. The average follow-up was 13 months (range, 9 to 40 months). Ninety-eight percent of the patients were able to return to full activities without pain at final follow-up. The minor complication rate (transient symptoms) was 20%. Clinically significant (major) complications (continued symptoms or revisionary surgery) occurred in 10% of patients. This study indicates that lateral ankle ligamentous incompetence, combined peroneal brevis and longus tears, and low-lying peroneus muscle belly commonly coexist in patients with peroneal tendon injuries. Appropriate surgical intervention of peroneal tendon tears and their coexisting pathology yields successful and predictable results with few clinically significant complications.

Adolescent↗

PubMedDate not supplied

Stability of the offset V osteotomy: effects of fixation, orientation, and surgical translocation in polyurethane foam models and preserved cadaveric specimens.

Polyurethane foam models and cadaver specimens were used to examine the stability of the offset V first metatarsal osteotomy. Uniform osteotomies were performed in all specimens by using a specially designed jig. Specimens in the polyurethane foam model series (n = 10) varied with respect to fixation type, fixation orientation, and degree of lateral translocation of the osteotomy. All specimens were loaded to failure in an Instron testing machine (Instron, Canton, MA). The plantar wing-pin (Kirschner wire) osteotomy group showed statistically significantly greater stiffness (P =.0119) and load at failure (P =.0027) than the dorsal wing-pin group. Cadaveric offset V specimens received the same amount of capital fragment lateral translocation but had different fixation types and orientations. Using the identical protocol as the models, the cadaveric dorsal wing-screw group showed statistically significantly less displacement at failure than the plantar wing-screw, plantar wing-pin, and dorsal wing-pin groups (P =.0262). The dorsal wing-pin group with a synthetic tension band showed a statistically significant greater stiffness (P =.0054) and peak load at failure (P =.0004) compared with the dorsal wing-pin group without the tension band. The most stable offset V construct in the polyurethane foam model was the plantar wing-pin group. The preserved cadaveric specimens yielded different results. The cadaveric dorsal wing-pin group with the synthetic tension band showed superior stability compared with all other non-tension-band groups. These results indicate the importance of tension band effects provided by capsular and ligamentous structures, which are typically ignored in surgical optimization research.

Biomechanical Phenomena↗

PubMedDate not supplied

Magnetic resonance imaging and surgical correlation of peroneus brevis tears.

This study reviewed retrospectively preoperative magnetic resonance imaging (MRI) and intraoperative findings of 32 patients who underwent surgical treatment of longstanding peroneus brevis tendon pathology. The purpose of this study was 3-fold: 1) to determine the sensitivity and specificity of MRI diagnosis of peroneus brevis tendon tears as confirmed by surgical findings, 2) to define the prevalence of osseous and soft-tissue pathologies that coexist with peroneus brevis injuries, and 3) to compare the occurrence rates of other associated pathologies found on MRI to that of the surgical findings. MRI diagnosis of a peroneus brevis tendon tear showed 83% sensitivity and 75% specificity to intraoperative findings. Four false positive and 2 false negative cases were identified. Coexisting conditions identified by MRI included a low-lying muscle belly/peroneus quartus (44%), anterior talofibular ligament rupture (50%), flattened/hypertrophy peroneus longus tendon (56%), increased signal intensity within peroneus longus tendon (53%), and a flat/convex fibular groove (78%). These results show that peroneus brevis tears rarely present as isolated injuries and support the need for a comprehensive preoperative clinical evaluation and MRI assessment of the entire lateral ankle complex.

Adolescent↗

PubMedDate not supplied

Multiplier method for prediction of adult height in patients with achondroplasia.

To date, the only way to predict adult height in achondroplastic dwarves has been to consult a growth chart. The purpose of this study was to ascertain whether the multiplier method of predicting adult height at skeletal maturity in healthy persons can be applied to persons with achondroplasia. Previous studies have shown that the multiplier method can be applied to lower limb length, upper limb length, total height, foot length, and foot height. It is therefore reasonable to suggest that the growth pattern for total height in achondroplastic dwarves might also be characterized by a multiplier. Total height multipliers for achondroplastic dwarves ("achondroplasia height multipliers") were calculated from two separate databases by dividing height at maturity by height at each respective age for both genders. Little variability was found among multipliers for each age and among multipliers calculated from different databases. Upper torso (sitting height) multipliers and lower limb multipliers were also derived for achondroplastic dwarves. Lower limb and total height growth rates were slower in achondroplastic dwarves compared with healthy persons. However, sitting height multipliers for achondroplastic dwarves were closely related to sitting height multipliers for healthy persons. Because these findings showed that the multiplier values were independent of population and percentile, the multiplier method may be a valid method for quickly predicting height at any age for achondroplastic dwarves.

Achondroplasia↗

PubMedDate not supplied

Multiplier method for predicting adult foot length.

Lower and upper limb lengths and total height can be predicted by the multiplier method. The multiplier is a coefficient that corresponds to each age and gender. The coefficient for any age can be multiplied by the length at that age to give the length at skeletal maturity. Our purpose was to calculate foot length multipliers and determine whether they are independent of percentile, much like the multipliers for lower and upper limb lengths and total height. Foot length multipliers were calculated from 3 separate previously published databases of foot length in children. The multipliers were calculated by dividing foot length at maturity by foot length at each respective age for each percentile and for both genders. The multiplier values for each percentile group at each age were found to be relatively equivalent, with little variability (as was found for the validated multipliers for lower limb length and total height). Also, little variability was found among multipliers calculated from different databases. In addition, we compared foot length multipliers with lower limb, upper limb, and total height multipliers. Compared with lower limb (tibial and femoral) multipliers, the foot length multipliers were significantly different because the foot achieves a higher percentage of maturity length earlier than does the femur or tibia. Because prediction of limb length and limb length discrepancy can be achieved accurately by using the lower limb multiplier, it is also likely that the foot length multiplier can be used to predict foot length and foot length discrepancy at maturity.

Adolescent↗

PubMedDate not supplied

Gastrocnemius soleus recession: a simpler, more limited approach.

Multiple surgical procedures have been described for the correction of equinus deformity. We present a review of the anatomy, biomechanics, and clinical assessment of equinus. In addition, we provide a detailed surgical technique for gastrocnemius soleus recession and introduce an anatomical guide for surgical treatment.

Biomechanical Phenomena↗

PubMedDate not supplied

Static rearfoot alignment: a comparison of clinical and radiographic measures.

Foot structure is typically evaluated using static clinical and radiographic measures. To date, the literature is devoid of a correlation between rearfoot frontal plane radiographic parameters and clinical measures of alignment. In a repeated-measures study comparing radiographic and clinical rearfoot alignment in 24 healthy subjects, radiographic angular measurements were made from standard weightbearing anteroposterior, lateral, long leg calcaneal axial, and rearfoot alignment views. Clinical measurements were made using a jig and scanner to assess the malleolar valgus index and a goniometer to evaluate the resting and neutral calcaneal stance positions. There was a significant correlation between frontal plane radiographic angles (long leg calcaneal axial and rearfoot alignment views) (r = 0.814). Similarly, there was a significant correlation between clinical measures (resting calcaneal stance position and malleolar valgus index) (r = 0.714). A multivariate stepwise regression showed that resting calcaneal stance position can be accurately predicted from 3 of the 15 clinical and radiographic measurements collected: malleolar valgus index, rearfoot alignment view, and long leg calcaneal axial view (r = 0.829). In summary, a commonly used clinical measure of static rearfoot alignment, resting calcaneal stance position, was correlated closely with the malleolar valgus index and both frontal plane radiographic parameters.

Adult↗

PubMedDate not supplied

Subtalar joint arthrodesis.

Forty patients (12 men and 28 women) treated with isolated subtalar joint arthrodesis were retrospectively reviewed. The average patient age was 50 years (range, 21-76 years). Preoperative diagnoses included posterior tibial tendon dysfunction, post-traumatic arthritis, nontraumatic arthritis, and subtalar joint middle facet coalition. The average follow-up was 15 months (range, 12-74 months). Subjective postoperative questionnaire results were classified as satisfied (n = 32), satisfied but with reservations (n = 4), or dissatisfied (n = 4). Eighty-three percent of the patients (n = 33) stated that they would undergo the procedure again. Minor complications (those that resolved with nonoperative treatment) occurred in 55% of the patients. However, the major complication rate was only 12.5%. This study showed no statistical correlation between the preoperative diagnosis and the postoperative outcome. Our results also suggested that the prevalence of complications is slightly higher than in previous reports. Isolated subtalar joint arthrodesis is an effective treatment for pain and deformity of the rearfoot.

Adult↗

PubMedDate not supplied

Realignment arthrodesis of the rearfoot and ankle: a comprehensive evaluation.

Ankle and tibiotalocalcaneal arthrodeses are performed for the treatment of painful, arthritic, unstable, and deformed rearfoot and ankle joints. Surgical complications are not uncommon (approximately 30%); some can be attributed to poor preoperative planning and inadequate intraoperative position. Several authors have attempted to define the optimal position for ankle arthrodesis without objective multiplanar radiographic analysis and consistent reference points. This investigation explored the effects of ankle and tibiotalocalcaneal realignment arthrodeses on static lower-extremity position in 20 patients. The most common preoperative diagnosis was severe degenerative joint disease following ankle fractures and ankle instability. Seven tibiotalocalcaneal arthrodeses and 13 isolated ankle arthrodeses were performed (mean follow-up, 22 months). Average time to radiographic osseous union of the isolated ankle and tibiotalocalcaneal arthrodeses was 11 and 7 weeks, respectively. Medical complications occurred in 2 patients (10%). There were no statistically significant differences between preoperative and postoperative angular relationships. This study objectively quantifies multiplanar foot-to-leg realignment and defines the optimal clinical and radiographic positions for ankle and tibiotalocalcaneal realignment arthrodeses.

Ankle↗