Takaaki Shinohara

Importance of distal radioulnar joint arthroscopy for evaluating the triangular fibrocartilage complex

BackgroundThe present study evaluated the importance of visualizing both sides of the triangular fibrocartilage complex (TFCC) when diagnosing ulnar wrist pain.MethodsA total of 20 patients with ulnar wrist pain who underwent both radiocarpal joint (RCJ) and distal radioulnar joint (DRUJ) arthroscopy were studied retrospectively. TFCC was graded as normal or as having wear or tear. The definitive diagnosis was made by evaluating the TFCC from both joints. The medical records were reviewed to document the preoperative diagnosis, arthroscopic findings, postoperative diagnosis, and operative procedure(s) performed after the arthroscopic examinations. The patients’ status at final follow-up was evaluated using the modified Green and O’Brien wrist scoring system. The TFCC grading on RCJ and DRUJ arthroscopies was compared.ResultsThe final diagnosis was modified after arthroscopic examination in three cases (15%). In six patients (30%), DRUJ arthroscopy revealed pathological TFCC findings that could not be detected on RCJ arthroscopy. The DRUJ arthroscopy detected wear or degenerative changes seen only on the proximal aspect of the TFCC in four patients and tear in two patients. On the other hand, in only one patient (5%) were there no pathological findings observed from the DRUJ portal, although RCJ arthroscopy found wear. In eight patients (45%), the arthroscopic grading of TFCC was the same on RCJ and DRUJ arthroscopy; of these, the TFCC was graded as normal in one patient, showing wear in three patients, and with a tear in five patients. For diagnosing TFCC pathology, RCJ arthroscopy had a sensitivity of 68% and a negative predictive value (NPV) of 14%, whereas the sensitivity was 95% and the NPV was 50% for DRUJ.ConclusionsAdding DRUJ arthroscopy to RCJ arthroscopy enables more accurate diagnosis of TFCC pathology because the proximal aspect of the articular disk and the foveal insertion of the distal radioulnar ligament can be visualized.

Clinical, Radiographic, and Arthroscopic Outcomes After Ulnar Shortening Osteotomy: A Long-Term Follow-Up Study

PURPOSE Previous studies have investigated the long-term outcomes of ulnar shortening osteotomy (USO) in the treatment of ulnocarpal abutment syndrome (UCA), but none have used arthroscopic assessments. The purpose of this study was to investigate the long-term clinical outcomes of USO with patient-based, arthroscopic, and radiographic assessments. METHODS We retrospectively reviewed 30 patients with UCA after a minimum follow-up of 5 years, with arthroscopic evaluations at the time of both USO and plate removal. We confirmed the initial diagnosis of UCA by radiography and arthroscopy. Mean age at the time of index surgery was 37 years. Mean duration of follow-up was 11 years (range, 5-19 y). We obtained Disabilities of the Arm, Shoulder, and Hand and Hand20 self-assessments postoperatively for all patients. Bony spur formation was evaluated postoperatively from plain radiographs. RESULTS We detected triangular fibrocartilage complex (TFCC) disc tear in 13 wrists arthroscopically at the time of USO. Of these, 10 showed no evidence of TFCC disc tear at second-look arthroscopy. The remaining 17 cases showed no TFCC disc tear at either first- or second-look arthroscopy. Follow-up radiography revealed that bony spurs at the distal radioulnar joint had progressed in 13 wrists. Disabilities of the Shoulder, Arm, and Hand and Hand20 scores did not significantly correlate with the presence of bony spurs or TFCC disc tears. Range of motion decreased significantly with age only. Lower grip strength correlated with bony spur and lower radial inclination. Triangular fibrocartilage complex tear, male sex, and advanced age were associated with lower Disabilities of the Shoulder, Arm, and Hand and Hand20 scores. CONCLUSIONS Ulnar shortening osteotomy achieved excellent long-term results in most cases. Most TFCC disc tears identified at the initial surgery had healed by long-term arthroscopic follow-up. We suggest that UCA with a TFCC disc tear is a good indication for USO.

Sonography-guided Arthroscopy for Wrist Ganglion

PURPOSE To describe how to combine the complementary features of sonography and arthroscopy to make the arthroscopic resection of wrist ganglions a safer and more reliable surgery. METHODS A total of 22 patients with wrist ganglions had sonography-assisted arthroscopic resection. Sonographic visualization of ganglions, adjacent structures (ie, vessels, nerves, and tendons), and the cycling tip of the arthroscopic shaver was assessed. Arthroscopic visualization of the ganglions or ganglion stalk was also assessed. Clinical outcome measures included wrist range of motion, grip strength, and our patient-rated Hand 20 questionnaire. RESULTS Sonographic visualization of the ganglion stalk, adjacent structures, and the cycling tip of the arthroscopic shaver was possible in all 22 cases. However, ganglion stalks were visualized by arthroscopy in only 4 cases. The mean range of motion and grip strength were not significantly changed following surgery. However, the mean Hand 20 score was significantly improved from 17 to 6 at final follow-up. Ganglion recurrence was seen in 2 cases at 6 and 8 months after surgery. CONCLUSIONS Sonography-guided wrist arthroscopy provides several advantages for surgeons, including visualization of the ganglions and ganglion stalk, as well as of the arthroscopic shaver and adjacent structures such as nerves, vessels, and tendons to perform surgery safely.

Simple debridement has little useful value on the clinical course of recalcitrant ulnar wrist pain

The purpose of this study was to evaluate treatment results following arthroscopic triangular fibrocartilage complex (TFCC) debridement for recalcitrant ulnar wrist pain. According to the treatment algorithm, 66 patients (36 men and 30 women with a mean age of 38.1 years (15 to 67)) with recalcitrant ulnar wrist pain were allocated to undergo ulnar shortening osteotomy (USO; n = 24), arthroscopic TFCC repair (n = 15), arthroscopic TFCC debridement (n = 14) or prolonged conservative treatment (n = 13). The mean follow-up was 36.0 months (15 to 54). Significant differences in Hand20 score at 18 months were evident between the USO group and TFCC debridement group (p = 0.003), and between the TFCC repair group and TFCC debridement group (p = 0.029). Within-group comparisons showed that Hand20 score at five months or later and pain score at two months or later were significantly decreased in the USO/TFCC repair groups. In contrast, scores in the TFCC debridement/conservative groups did not decrease significantly. Grip strength at 18 months was significantly improved in the USO/TFCC repair groups, but not in the TFCC debridement/conservative groups. TFCC debridement shows little benefit on the clinical course of recalcitrant ulnar wrist pain even after excluding patients with ulnocarpal abutment or TFCC detachment from the fovea from the indications for arthroscopic TFCC debridement.

Regeneration of the perineurium after microsurgical resection examined with immunolabeling for tenascin-C and alpha smooth muscle actin

The regenerative process of the perineurium and nerve function were examined using an in vivo model of perineurium resection in the rat sciatic nerve. Our hypothesis is that the regenerative process of the perineurium can be demonstrated by immunolabeling for tenascin‐C and alpha smooth muscle actin after microsurgical resection of the perineurium in vivo. A total of 38 Lewis rats were used. Eight‐week‐old animals were assigned to one of two groups: the epi‐perineurium removal group or the sham group. Under operative microscopy, the sciatic nerve was dissected from surrounding tissues at the thigh level from the ischial tuberosity to the fossa poplitea. The epi‐perineurium was carefully removed by cutting circumferentially and stripping distally for 15 mm. For CatWalk® dynamic gait analysis, only right sciatic nerves underwent surgery; the left sciatic nerves were left intact. For pathological and electrophysiological tests, both the right and left sciatic nerves underwent surgery. Analysis of data was performed at each time interval with a two‐group t‐test. P < 0.05 was considered statistically significant. After resection of a 15‐mm section of the epi‐perineurium, immediate endoneurial swelling occurred in the outer portion and spread into the central portion. Although demyelination and axonal degeneration were found in the swollen area, remyelination and recovery of electrophysiological function were seen after regeneration of the perineurium. An immunohistological and electron microscopic study revealed that the perineurium regenerated via fusion of the residual interfascicular perineurium and endoneurial fibroblast‐like cells of mesenchymal origin. CatWalk gait analysis showed not only motor paresis but also neuropathic pain during the early phases of this model.

Cubital tunnel syndrome caused by amyloid elbow arthropathy in long-term hemodialysis patients: report of 4 cases.

Carpal tunnel syndrome occurs frequently in long-term hemodialysis patients. However, the literature contains few detailed reports of other nerve entrapment syndromes of the upper extremity in these patients. We encountered 4 cases in which cubital tunnel syndrome occurred in long-term hemodialysis patients. In all cases, a hypertrophic synovial mass projecting from the humeroulnar joint compressed the ulnar nerve, and Congo red staining revealed that the mass contained amyloid deposition. Synovial proliferation resulting from amyloid arthropathy of the elbow joint appears to be the primary cause of this disease.

Pathomechanical Significance of Radial Head Subluxation in the Onset of Osteochondritis Dissecans of the Radial Head

Osteochondritis dissecans of the elbow mainly involves the capitellum; however, no authors have reported the condition in the radial head with subluxation of the radial head. We report four cases in which osteochondritis dissecans involved the radial head and was accompanied by radial head subluxation. All patients were male and their ages ranged from 11 to 13 years (average, 11.8 years). All lesions were located at the posteromedial aspect of the radial head with anterior subluxation of the radial head. Fragment removal was performed in one case and ulnar osteotomy in two cases; the remaining case was treated conservatively with the prohibition of sports. Three cases had a good outcome, whereas obvious anterior subluxation of the radial head and limitation of elbow flexion remained in the case treated with fragment removal.

Arthroscopic findings of Kienbock's disease

PurposeKienböck’s disease affects the lunate bone, and osteoarthritic changes progress as the disease advances; however, relatively few studies have reported the arthroscopic findings of Kienböck’s disease, and these reports have been in small populations. The purpose of this study was to review arthroscopic findings in a larger population than studied in previous reports.MethodsWe retrospectively reviewed 57 patients who underwent radial osteotomy for Kienböck’s disease after arthroscopy of both the radiocarpal and midcarpal joints. All arthroscopic findings were classified as follows in terms of the location of osteoarthritic changes: lunate fossa of the radius, proximal/distal surface of the lunate bone, and capitate head. Radiological stages were classified according to the modified Lichtman’s classification system.ResultsAll but two patients had cartilage lesions in the proximal lunate cartilage. Older patients had significantly more cartilage lesions, but radiological stage showed no correlation with the number of cartilage lesions.ConclusionsThis study demonstrated that the proximal lunate bone was affected in most cases of Kienböck’s disease and that older patients had more cartilage lesions.

Painful Snapping Elbow in Patients With Congenital Radioulnar Synostosis: Report of Two Cases

Two patients with congenital radioulnar synostosis presented with painful snapping on elbow motion in one case and locking of the elbow joint in the other. Elbow arthroscopy revealed the presence of tight fibrous tissue trapping the radial head. Arthroscopic removal of this tight fibrous tissue resulted in painless joint motion without recurrence of snapping or locking.

Ulnar impaction syndrome: incidence of lunotriquetral ligament degeneration and outcome of ulnar-shortening osteotomy.

PURPOSE We hypothesized that most patients with ulnar impaction syndrome have degenerative changes of the proximal lunotriquetral (LT) membrane and that ulnar-shortening osteotomy is an effective procedure in these patients. METHODS We retrospectively reviewed 50 wrists of 49 patients with idiopathic ulnar impaction syndrome who underwent an arthroscopic evaluation at the time of ulnar-shortening osteotomy, and subsequently at plate removal. Based on the Geissler classification, patients were divided into group A, normal, and group B, grades I to IV. The degree of degeneration of the proximal LT membrane at first-look arthroscopy was compared with that at second-look arthroscopy. RESULTS After ulnar-shortening osteotomy, both groups improved significantly in wrist range of motion and grip strength. According to the Mayo wrist score, 29, 18, and 3 patients showed excellent, good, and fair results, respectively. Of the 50 wrists, 25 had degenerative changes (group B) in the proximal LT membrane at the time of first-look arthroscopy. Of the 25 wrists in group B, 11 wrists improved based on the Geissler grade, 9 wrists showed no changes, and 2 wrists became worse. Clinically, patients demonstrated improvement after ulnar-shortening osteotomy regardless of the degree of degenerative LT ligament changes. CONCLUSIONS Degenerative LT membrane changes that were seen in about half of our patients were mostly of a mild nature, and the clinical outcomes of ulnar-shortening osteotomy were acceptable. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.