[Myoepithelial tumors of soft tissue: A case of mixed tumor]. / Tumeurs myoépithéliales des tissus mous : à propos d'un cas de tumeur mixte.

Myoepithelial neoplasms of soft tissue represent a rare entity which has been described only recently when compared to salivary gland tumors with whom they share histopathological and molecular features. The most common locations are the superficial soft tissues of the limbs and limb girdles. However, they can rarely occur in the mediastinum, abdomen, bone, skin and visceral organs. Benign forms (myoepithelioma and mixed tumor) are more frequent than myoepithelial carcinoma and the latter mostly affects children and young adults. Diagnosis is mainly based on histology, which shows a proliferation of myoepithelial cells of variable morphology with or without glandular structures in a myxoid background, and immunohistochemistry, which shows co-expression of epithelial and myoepithelial markers. Molecular tests are not mandatory, but in selected cases FISH analysis can prove useful as about 50% of myoepitheliomas show EWSR1 (or rarely FUS) rearrangements and mixed tumors show PLAG1 rearrangements. Here, we present a case of a mixed tumor of the soft tissue occuring in the hand with expression of PLAG1 in immunohistochemistry.

Surgical Treatment of Enchondromas of the Hand During Childhood in Ollier Disease.

PURPOSE: The objective of the present study was to evaluate the outcome of surgical treatment of hand lesions in Ollier disease (OD) carried out during childhood. METHODS: A retrospective review was carried out of 10 pediatric patients with hand involvement of OD, who had undergone surgery for metacarpal or phalangeal enchondromas. The technique comprised curettage and cortical bone reconstruction with corticoplasty, to restore a near-normal phalangeal volume. The range of finger motion (pulp-to-palm distance), the shortened Disabilities of the Arm, Shoulder, and Hand (QuickDASH) questionnaire score, cosmetic improvement, radiological findings (according to Tordai's classification), and recurrence were recorded after a mean follow-up of 7.5 years (range, 4-11.3 years). RESULTS: The mean age at surgery was 10.7 years (range, 6-14 years). Curettage was performed on 35 enchondromas, and 9 cavities were filled with a bone graft. The mean pulp-to-palm distance was significantly lower after surgery (from 1.5 cm to 0.25 cm; P < .05). The mean QuickDASH score was 3.84 (range, 0-11.4). A marked cosmetic improvement was noted for 83% of the hands. Three enchondromas recurred in 1 patient, requiring a second curettage. Fifty-seven percent of the cavities were completely filled with bone (Tordai stage 1) at last follow-up. The outcome did not depend on the presence or absence of a bone graft. CONCLUSIONS: Our results suggest that early surgical treatment comprising curettage and corticoplasty leads to good clinical, cosmetic, and radiological outcomes. Early surgical treatment of well-developed and/or symptomatic enchondromas of the hand in OD should be considered. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Feasibility of arthroscopic decompression of the axillary nerve in the quadrilateral space: Cadaver study.

INTRODUCTION: Axillary nerve compression is a rare, but disabling condition. The three main causes are quadrilateral space syndrome among young athletes, compression due to an inferior glenohumeral osteophyte in early osteoarthritis and isolated teres minor atrophy secondary to triceps hypertrophy. The diagnosis is clinical, but may be reinforced by an electromyogram or corticosteroid injection. The usual surgical treatment is open nerve decompression using a posterior approach. Arthroscopy is a less invasive approach that should be useful in theory. HYPOTHESIS: Arthroscopic decompression of the axillary nerve is safe and less invasive than open techniques. MATERIAL AND METHODS: Arthroscopic nerve decompression was performed as described by PJ Millet and TR Gaskill on 10 shoulders from 6 frozen cadavers. An open posterior approach was then made to verify the effectiveness of the nerve decompression. RESULTS: The axillary nerve and its branches, the circumflex artery and the triceps were always sufficiently released in the space below the joint capsule. When the joints were subsequently opened by a posterior approach, complete nerve decompression was confirmed in all cases with no iatrogenic lesions. DISCUSSION: The good results of this study are encouraging, but should be supplemented with a comparative study in patients of open versus arthroscopic axillary nerve release. CONCLUSION: We think this arthroscopic technique is a good option for treating axillary nerve compressions. The complication risk is expected to be low. LEVEL OF EVIDENCE: IV.

Partial arthroscopic trapeziectomy and stabilisation by ligamentoplasty: Outcomes in patients younger than 60years.

BACKGROUND: Thumb carpometacarpal joint (TCMJ) osteoarthritis is the fourth leading cause of referral to elective hand surgery. None of the available techniques has proved superior over the others. Some techniques carry unacceptable risks for younger patients, such as loss of strength and shortening of the thumb column after total trapeziectomy, or wear and loosening after total arthroplasty. Our objective was to assess outcomes after partial arthroscopic trapeziectomy (PAT) combined with suspensionplasty using the abductor pollicis longus (APL) tendon in patients younger than 60years of age. HYPOTHESIS: PAT combined with suspensionplasty using the APL tendon in patients younger than 60years would restore strength in the medium-term without further surgery. MATERIAL AND METHODS: We retrospectively included consecutive patients operated between 2007 and 2017, in a single centre, and aged less than 60years. All patients had isolated TCMJ osteoarthritis stage 1 to 3 according to Eaton and Glickel classification that remained symptomatic despite optimal conservative treatment. We collected pain intensity, range of motion, strength, the Nelson Hospital Score (NHS), and the Patient-Rated Wrist Evaluation (PRWE) score. Radiographs were reviewed. RESULTS: We included 27 patients, of whom 6 had surgery on both thumbs, yielding 33 thumbs for the analysis. Mean follow-up was 64.7months (range: 10.6-136.5months). Pain intensity, grip strength, and key-pinch strength were significantly improved (p<0.001), with no difference between men and women. No differences were found for the Kapandji score (p=0.2) or TCMJ hyperextension (p=0.06). At last follow-up, the mean NHS was 83.2±19.4 and the mean PRWE was 15.4±17.9. Mean sick leave duration was 5.4weeks (range: 1-24weeks). Only 2 patients, both in manual jobs, were unable to return to work. The radiographs at last follow-up showed the development of moderate TCMJ narrowing in 14 patients and evidence of scapho-trapezio-trapezoid (STT) osteoarthritis in 10 patients. No patient experienced complex regional pain syndrome or injury to the sensory branch of the radial nerve. A single patient required further surgery for persistent pain. DISCUSSION: Patients younger than 60years who are treated with this minimally invasive technique are likely to experience sustained improvements in both strength and pain intensity. Total trapeziectomy and pyrocarbon implant has also been evaluated in younger patients, who experienced pain relief and strength gains but had lower levels of satisfaction and developed complications inherent in the implants. The short time off work and low morbidity make our technique a procedure of choice in younger patients. To build on this study, a comparison of PAT and arthroplasty would be of interest. LEVEL OF EVIDENCE: IV.