Faculty Bibliography

PURPOSE/OBJECTIVE:We report 8 cases of acute or subacute unilateral nondissociative carpal instability (CIND) in the context of nondisplaced scaphoid fractures. METHODS:Eight patients from 3 centers developed abnormal volar intercalated segment instability (VISI) or dorsal intercalated segment instability (DISI) following the diagnosis of a nondisplaced scaphoid fracture. An operative inspection in each patient confirmed intact scapholunate and lunotriquetral interosseous ligaments. We outline the demographic characteristics of our patient cohort, radiologic and operative findings of CIND-DISI and CIND-VISI, and the outcomes of acute and delayed treatment. RESULTS:Two patients were diagnosed with CIND-DISI and 6 with CIND-VISI associated with ipsilateral nondisplaced scaphoid fractures. The average time from injury to diagnosis of CIND was 11 weeks, and the mean clinical and radiographic follow-up was 18 months. Rapid healing of the scaphoid fractures was achieved in all patients (4 open reduction internal fixation, 4 cast). All patients underwent surgery to improve proximal carpal row alignment: in 3 of the 4 patients who were diagnosed and treated surgically within 12 weeks of injury, the radiolunate angle (RLA) was successfully restored. A contracture release and ligament repair or reconstruction with tendon graft 12 or more weeks following injury was unsuccessful in restoring proximal row alignment in all 4 patients. Two patients in the delayed treatment group required secondary surgery for partial fusion. CONCLUSIONS:Based on the arthroscopic, imaging, and operative findings, we propose that the ligamentous restraints to CIND-VISI are dorsal at the radiocarpal joint and volar at the midcarpal joint. Conversely, the ligamentous restraints to CIND-DISI are dorsal at the midcarpal joint and volar at both the radiocarpal and midcarpal joints. In our series, a delayed diagnosis and late reconstructive surgery were associated with no improvement in RLA. We recommend early recognition of traumatic CIND and prompt treatment of injured ligaments prior to the development of a fixed deformity. TYPE OF STUDY/LEVEL OF EVIDENCE/METHODS:Therapeutic V.

BACKGROUND: The importance of the radial head to elbow function and stability is increasingly apparent. Although preservation of the native radial head is preferred, severely comminuted fractures may necessitate resection or arthroplasty. Silastic radial head arthroplasty has been condemned on the basis of several sporadic reports of silicone synovitis. However, problems of "overstuffing," cartilage wear, and motion loss are becoming apparent with metal prostheses, indicating this also is not an ideal solution. Thus, the choices remain controversial. QUESTIONS/PURPOSES: We asked whether intact or reconstructed primary elbow stabilizers permit use of silastic radial head implants without fragmentation, failure, and silicone synovitis. METHODS: We retrospectively reviewed 23 patients with unreconstructable radial head fractures who were treated with silastic radial head arthroplasty and concomitant repair and/or reconstruction of the medial ulnar collateral ligament and/or lateral ulnar collateral ligament. Analysis included range of motion, pain, stability, and radiographic assessments; Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire; and Mayo Elbow Performance Score (MEPS). The minimum followup was 16 months (average, 69.6 months; range, 16-165 months). RESULTS: At last followup, the mean elbow flexion was 145 degrees , extension 11 degrees , supination 80 degrees , and pronation 83 degrees . The mean MEPS score was 88.9. The mean DASH score was 11.8. There were eight reoperations, none resulting from failure of the radial head implants. CONCLUSIONS: These results demonstrate silastic radial heads can be used with low complication rates and without evidence of synovitis when concomitant elbow ligament repair or reconstruction is performed. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

This research examined developmental continuity between "cruising" (moving sideways holding onto furniture for support) and walking. Because cruising and walking involve locomotion in an upright posture, researchers have assumed that cruising is functionally related to walking. Study 1 showed that most infants crawl and cruise concurrently prior to walking, amassing several weeks of experience with both skills. Study 2 showed that cruising infants perceive affordances for locomotion over an adjustable gap in a handrail used for manual support, but despite weeks of cruising experience, cruisers are largely oblivious to the dangers of gaps in the floor beneath their feet. Study 3 replicated the floor-gap findings for infants taking their first independent walking steps, and showed that new walkers also misperceive affordances for locomoting between gaps in a handrail. The findings suggest that weeks of cruising do not teach infants a basic fact about walking: the necessity of a floor to support their body. Moreover, this research demonstrated that developmental milestones that are temporally contiguous and structurally similar might have important functional discontinuities.

PURPOSE/OBJECTIVE:Watson and Ballet introduced the concept of a direct association between scapholunate (SL) dissociation and radioscaphoid (RS) arthritis with preservation of the radiolunate (RL) articulation in 1984. This principle has served as the anatomic, biomechanical, and pathophysiological basis for reconstructive surgery in the carpus. Recently, we have noted cases of concurrent SL dissociation and RL arthritis without RS arthritis, which is contrary to the accepted concept of wrist arthritis due to SL advanced collapse. The purpose of this study was to determine whether Watson and Ballet's thesis that SL dissociation results in RS joint degeneration with sparing of the RL joint can be confirmed, or whether another joint degeneration pattern can be associated with SL dissociation. METHODS:The 3 authors independently reviewed 897 radiographs of the wrist in 691 male patients (206 bilateral and 485 unilateral) with diagnosis codes of wrist osteoarthritis (715.13), wrist instability (718.83), and wrist sprain (842.00). Posterior-anterior, oblique, and lateral views were available for all wrists. Elements assessed were RS joint, RL joint, SL joint, midcarpal joint, ulnar variance, ulnolunate joint, SL angle, and lunocapitate angle. RESULTS:There were 146 wrists with radiographic SL dissociation. Nine wrists in 6 patients had radiographic SL dissociation and RL arthritis but no RS arthritis. An additional 6 wrists in 6 patients had radiographic RL arthritis but no SL dissociation or RS arthritis; however, 5 of these did have an SL angle of 60 degrees or greater. CONCLUSIONS:Our results show that RL arthritis can occur in association with SL dissociation, and that the generally held view that the RL articulation is spared in SL advance collapse is not universally true. Consequently, it is our recommendation that both the RL and RS joints should be carefully evaluated for degenerative changes when planning treatment for patients with SL dissociation, because it should not be assumed that the RL joint has been spared.

Symptomatic articular cartilage lesions have gained attention and clinical interest in recent years and can be difficult to treat. Historically, various biologic surgical treatment options have yielded inconsistent results because of the inferior biomechanical properties associated with a variable healing response. Improving technology and surgical advances has generated considerable research in cartilage resurfacing and optimizing hyaline tissue restoration. Biologic innovation and tissue engineering in cartilage repair have used matrix scaffolds, autologous and allogenic chondrocytes, cartilage grafts, growth factors, stem cells, and genetic engineering. Numerous evolving technologies and surgical approaches have been introduced into the clinical setting. This review will discuss the basic science, surgical techniques, and clinical outcomes of novel synthetic materials and scaffolds for articular cartilage repair.

The repair of diseased or damaged cartilage remains one of the most challenging problems of musculoskeletal medicine. Tissue engineering advances in cartilage repair have utilized autologous and allogenic chondrocyte and cartilage grafts, biomaterial scaffolds, growth factors, stem cells, and genetic engineering. The mesenchymal stem cell has specifically attracted much attention because of its accessibility, potential for differentiation, and manipulability to modern molecular, tissue and genetic engineering techniques. Mesenchymal stem cells provide invaluable tools for the study of tissue repair when combined with a carrier vehicle/matrix scaffold, and/or bioactive growth factors. However, an underappreciated source of knowledge lies in the relationship between fetal development and adult tissue repair. The multitude of events that take place during fetal development which lead from stem cell to functional tissue are poorly understood. A more thorough understanding of the events of development as they pertain to cartilage organogenesis may help elucidate some of the unknowns of adult tissue repair.