The modified Smith–Petersen and Kocher–Langenbeck approaches were used to expose the lateral cutaneous nerve of the thigh and the femoral, obturator and sciatic nerves in order to study the risk of injury to these structures during the dissection, osteotomy, and acetabular reorientation stages of a Bernese peri-acetabular osteotomy.

Injury of the lateral cutaneous nerve of thigh was less likely to occur if an osteotomy of the anterior superior iliac spine had been carried out before exposing the hip.

The obturator nerve was likely to be injured during unprotected osteotomy of the pubis if the far cortex was penetrated by > 5 mm. This could be avoided by inclining the osteotome 45° medially and performing the osteotomy at least 2 cm medial to the iliopectineal eminence.

The sciatic nerve could be injured during the first and last stages of the osteotomy if the osteotome perforated the lateral cortex of ischium and the ilio-ischial junction by > 10 mm.

The femoral nerve could be stretched or entrapped during osteotomy of the pubis if there was significant rotational or linear displacement of the acetabulum. Anterior or medial displacement of < 2 cm and lateral tilt (retroversion) of < 30° were safe margins. The combination of retroversion and anterior displacement could increase tension on the nerve.

Strict observation of anatomical details, proper handling of the osteotomes and careful manipulation of the acetabular fragment reduce the neurological complications of Bernese peri-acetabular osteotomy.

Cite this article: Bone Joint J 2015;97-B:636–41.

Purpose of the study: Chronic lateral instability of the ankle is often associated with residual varus deformity of the rear foot and exaggerated plantar flexion of the first ray. Several surgical techniques have been described to treat this problem, but recurrence can occur if all the components of the instability are not corrected. The purpose oft his work was to present was to present a new diagnostic and therapeutic approach to the treatment of recurrent lateral instability of the ankle.

Material and methods: Eight patients with talipes cavovarus(9 feet) were treated for recurrent chronic instability of the ankle. All patients had undergone at least one prior procedure to stabilize the rear foot and suffered persistent pain as well as subjective ankle instability. Mean age was 25 years. All patients underwent a calcaneal osteotomy for lateralization and transfer of the long fibular onto the short fibular ligament, with an additional Bronström ligament reconstruction in four cases. Clinical and radiological follow-up was 37 months on average.

Results: All patients were very satisfied. The AOFAS score improved from 58 points preoperatively to 97 points (max 100 points) at last follow-up. Postoperative alignment of the rear foot was considered physiological in all cases.

Conclusion: Recurrent chronic lateral instability of the ankle is often associated with chronic misalignment of the rear foot, leading to gait disorders and persistent pain. Ligament insufficiency, varus misalignment, and over-solicitation of the long fibular should be investigated and treated with an individually adapted surgical procedure in order to correct the recurrent instability. The results of this approach have been very promising and have been associated with very strong patient satisfaction.

Purpose of the study: Recurrent deformity in adulthood after successful treatment of clubfoot in childhood is exceptional. Patients experience subjective instability of the hindfood associated with progressive varus deformity and osteoarthritis of the subtalar joint. The purpose of this study was to analyze outcome after double arthrodesis in the specific situation.

Material and methods: Nine patients aged 41 years on average (range 18–64 years) were reviewed clinically and radiologically at mean 43 months follow-up after double arthrodesis (subtalar and Chopart). Time between the primary surgery and arthrodesis was 25 years on average (range 8–37 years). Clinical outcome was assessed with the AOFAS system. Plain x-rays were analyzed.

Results: The AOFAS score improved from 42 points preoperatively to 67 points on average at last follow-up (maximum 90 points). Improvement in pain was less pronounced, 27 points preoperatively and 13 points at last follow-up. Ankle motion did not decrease significantly. There was a non-significant progression of the ankle joint osteoarthritic degeneration in 71% of patients. Subjectively, the patients were moderately satisfied with the postoperative alignment of the hindfoot.

Conclusion: Double arthrodesis is often the only alternative for adults with recurrent clubfoot deformity causing pain and subjective instability of the hindfoot. The results in our series did not reveal any significant progression of the ankle joint degeneration at midterm follow-up of three years. Pain and subjective instability were improved, though the physiological alignment of the hindfoot could not be totally restored.

Complete debridement for synovial chondromatosis of the hip joint is difficult to achieve by standard surgical approaches. The goal of this study was to report preliminary experiences and results for treatment of this disease by a recently developed technique for surgical dislocation of the hip. The technique offers a safe and entire access to the hip joint in order to perform a synovectomy and complete joint debridement. This technique was applied in 8 patients with mean age of 38 years (24–65yrs.). This was done as the initial treatment in 6 patients and for recurrent disease after previous surgery in 2 patients. The mean follow-up was 4.3 years (2–10yrs.). None of the patients had recurrence of synovial chondromatosis. Six of 8 patients showed a good or excellent clinical result without progressive radiographic signs of osteoarthritis (OA). None of the patients developed avascular necrosis. 2 patients underwent total hip joint replacement after 5 and 10 years. One of these two patients had three previous surgeries for recurrence. The other one had the surgical dislocation as initial treatment. Both presented with distinct radiographic signs of OA prior to the index surgery. The technique of surgical dislocation allowed a safe and reliable joint debridement for synovial chondromatosis of the hip. The results indicate that this approach is successful when performed at an early stage without distinct signs of OA.