Anatomic and biomechanical analysis of the arthroscopic wafer procedure

Algorithm-Guided Treatment of Ulna Impaction Syndrome: A 10-Year Follow-Up Study of Ulna Shortening Osteotomy and Wafer Procedure

Background: Ulnar impaction syndrome (UIS) is a common degenerative wrist condition which results from positive ulnar variance, leading to an overload on the ulnar carpus. Ulnar shortening osteotomy (USO) and the arthroscopic wafer procedure (AWP) are established therapies for UIS if conservative management fails. This study assessed an algorithm-guided treatment of UIS over a period of 10 years. Methods: This prospective observational study compared the outcome of 54 patients who underwent either USO or AWP for UIS based on a predefined treatment algorithm. The mean follow-up period was 10 years. Primary outcome parameters were the visual analogue scale (VAS) for pain and the Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH), whereas secondary outcome parameters were grip and pinch strength and range of motion. Results: The median preoperative ulnar variance was 2.6 mm in the USO group and 2.0 mm in the AWP group. The postoperative average ulnar variance was 0 mm in both groups. The preoperative pain at rest was 3.4 in the USO group and 2.3 in the AWP group. One year after surgery, there was a significant reduction to VAS 0.7 and 0.2, respectively. These results persisted to the 10-year follow-up (VAS 0.9 and 0.2). The pain in motion also decreased significantly in the first year (from 6.8 and 6.7 to 2.2 and 2.1), as well as after 10 years (2.4 and 1.0). The preoperative DASH score averaged 31.3 in the USO group and 35.8 in the AWP group. At the 10-year follow-up, the DASH of both groups decreased significantly to 4.35 in the AWP group compared to 12.7 in the USO group. Conclusions: Our data show that, when using our algorithm, both USO and AWP, two common operative treatment options of UIS, reliably reduce pain and significantly reduce the DASH score over at least a period of ten years. The results after 10 years differ from short-term results in so far as after one year, the USO group showed to some degree similar outcome parameters compared to AWP, whereas at the 10-year follow-up, AWP reached slightly better primary outcome parameters. The algorithm presented, thus, produced excellent short- and long-term outcomes. Our findings and the applied algorithm can assist in decision-making and patient education.

Reverse Wafer Procedure for Ulnar Impaction Syndrome

Ulnar impaction syndrome occurs when excessive load across the ulnocarpal joints results in pathologic changes, especially over the articular surface of the ulnar head and proximal ulnar corner of the lunate. The 2 main surgical options in ulnar impaction syndrome are ulnar shortening osteotomy and wafer procedure, whether open or arthroscopically, to decompress the ulnocarpal joint load. However, all of these techniques have their shortcomings and drawbacks. The current study demonstrates a novel technique to decompress the ulnocarpal joint load: the "reverse wafer procedure" for ulnar impaction syndrome. In this surgical technique, we resected the proximal ulnar side of the lunate instead of partial resection of the thin wafer of the distal ulnar head dome in the standard wafer procedure. This technique avoids iatrogenic central tear of triangular fibrocartilage and distal radioulnar joint portal arthroscopy, which is technically demanding while preserving the distal radioulnar joint.

Arthroscopic wafer procedure versus ulnar shortening osteotomy for ulnar impaction syndrome: a systematic review and meta-analysis

PURPOSE

This study aimed to systematically compare the efficacy and safety of arthroscopic wafer procedure (AWP) versus ulnar shortening osteotomy (USO) for ulnar impaction syndrome (UIS) treatment.

METHODS

All the studies included in this meta-analysis compared the efficacy of AWP to USO for UIS and were acquired through a comprehensive search across multiple databases. The meta-analysis was performed by calculating the effect sizes with the Cochrane Collaboration's RevMan 5.4 software.

RESULTS

A total of 8 articles were included in this analysis, comprising 148 cases in the AWP group and 163 cases in the USO group. The pooled estimates indicated no significant differences in combined Darrow's Criteria or Modified Mayo Wrist Score, Modified Mayo Wrist Score, DASH scores, grip strength, VAS score, and postoperative ulnar variation. On the other hand, the patients in the AWP group exhibited fewer complications (OR = 0.17, 95%CI 0.05-0.54, P = 0.003) and a lower reoperation rate (OR = 0.12, 95%CI 0.05-0.28, P < 0.00001) than those in the USO group.

CONCLUSIONS

The two surgical techniques were both effective in treating UIS but the AWP group showed fewer complications and a lower reoperation rate. Therefore, AWP may present a superior alternative for UIS treatment.

Is ulnar shortening osteotomy or the wafer procedure better for ulnar impaction syndrome?: A systematic review and meta-analysis

BACKGROUND

Wrist pain on the ulnar side is often caused by ulnar impaction syndrome (UIS). Idiopathic UIS requires surgical treatment when conservative treatment fails. The 2 main surgical procedures used are the wafer procedure and ulnar shortening osteotomy (USO) of the metaphysis or diaphysis. This review aimed to analyze comparative studies of the 2 procedures in UIS to determine clinical outcomes and complications.

METHODS

One prospective and 5 retrospective comparison trials were retrieved from the PubMed, Embase, and Cochrane Library databases. The primary outcomes were treatment effectiveness; pain visual analog scale (VAS), disabilities of the arm, shoulder, and hand (DASH) score, Mayo wrist, and Darrow scores. The incidence of postoperative complications formed the secondary outcome.

RESULTS

The selected studies included 107 patients who underwent the wafer procedure (G1) and 117 patients who underwent USO (G2). The wafer procedure had the benefits of less postoperative immobilization and an early return to work. However, there were no significant differences in the postoperative pain improvement and functional scores. All 6 studies reported high total complication rates and reoperation with USO. The most frequent complication was implant-related discomfort or irritation; subsequent plate removal was the most common reason for a secondary operation.

CONCLUSIONS

There was no difference in pain improvement or the postoperative functional score between the groups. Nevertheless, postoperative complications were the major pitfalls of USO. As the specialized shortening system advances further, a high-level study will be necessary to determine the surgical option in UIS.

Advances in wrist arthroscopic surgery in Indonesia

Since the 1990s, new insights in wrist arthroscopy have led to the introduction of numerous treatment methods. Consequently, therapeutic procedures are no longer limited to resection as more specialized repair and functional reconstruction methods, involving tissue replacement and essential structural augmentation, have been shown to be beneficial. This article discusses the most prevalent reasons and uses for wrist arthroscopy, with an emphasis on Indonesia’s most recent and major advances in reconstructive arthroscopic surgery. Joint debridement, synovectomy, ganglionectomy, capsular release, and osteotomies are frequent resection operations. Ligament repair and arthroscopy-aided reduction and fixation for fractures and nonunion are all examples of reconstructive surgery.

Results of isolated ulnar shaft shortening osteotomy in the treatment of idiopathic ulnocarpal impaction syndrome

The objective of this study was to evaluate the results of isolated ulnar shaft shortening osteotomy (USSO) in the treatment of idiopathic ulnocarpal impingement syndrome. This was a two-center retrospective study. All patients older than 18 years who underwent isolated USSO for idiopathic ulnocarpal impingement syndrome between 2006 and 2016 were included. The outcome measures were: patient satisfaction, decrease in pain intensity, change in occupation, QuickDASH and PRWE functional scores, secondary palliative surgery suggesting failure of the ulnar shaft shortening osteotomy, and postoperative ulnar variance. The main complications were analyzed. Thirty-one patients were included. Twenty-six (84%) were satisfied with the procedure. At an average follow-up of 62 months, there was no secondary palliative surgery. Mean pain intensity on VAS was 7/10 (range, 2-10) and 1.7/10 (range, 0-6) preoperatively and postoperatively, respectively, for a mean decrease of 5.3 ± 2.6 points; this decrease was statistically significant (p &lt; 0.001). None of the manual workers had to alter their work. Mean postoperative QuickDASH score was 19.6/100 (range, 0-79.55) and mean postoperative PRWE score was 23/100 (range, 1-85). Mean postoperative ulnar variance was -0.5 mm. As for complications, 61% of patients (n = 19/31) had discomfort related to the plate; 9.7% (n = 3/31) had distal radioulnar osteoarthritis; 4% (n = 1/19) had a fracture after hardware removal; 13% (n = 4/31) had non-union. Despite a high rate of complications, the study confirmed the effectiveness, in terms of pain, of isolated USSO in the treatment of idiopathic ulnocarpal impingement syndrome. LEVEL OF EVIDENCE: IV; retrospective cohort.

Differentiated Approaches to Treat Lesions of the TFCC Based on new arthroscopic Classification

In this article, pathology of the TFCC lesions, image diagnosis and arthroscopic examination were described. According to the radiocarpal arthroscopic findings, TFCC lesions are classified into intra-disc lesions (Class 1), radial lesion (Class 2), peripheral disc lesions which indicate slight to moderate DRUJ instability (Class 3) and degenerative lesion (Class 4). The radioulnar ligament (RUL) lesions that indicate moderate to severe DRUJ instability were classified with staging system with DRUJ arthroscopic findings (Stage 1 to 5). Author's treatment algorism with wrist arthroscopic findings including DRUJ arthroscopy was demonstrated and along with this algorism, various arthroscopic and open techniques to treat TFCC injuries were selected and resulted in success. Precise diagnosis of the TFCC lesions helped to select an adequate treatment for each lesion.Dieser Artikel beschreibt die pathologischen Veränderungen des TFCC sowie deren Befunde in der Bildgebung und Arthroskopie. Am TFCC lassen sich mittels Arthroskopie bei Sicht von radiokarpal zentrale (Typ 1), radiale (Typ 2) sowie periphere Läsionen (Typ 3), die mit einer moderaten Instabilität des distalen Radioulnargelenkes (DRUG) einhergehen, und degenerative Läsionen (Typ 4) unterscheiden. Läsionen der radioulnaren Bänder, die mit einer moderaten bis ausgeprägten Instabilität des DRUG vergesellschaftet sind, werden anhand der Befunde bei der DRUG-Arthroskopie in fünf Stadien eingeteilt. Diesen unterschiedlichen Befunden angepasst wurde ein Behandlungsalgorithmus mit verschiedenen arthroskopischen und offenen Verfahren entwickelt, der sich als erfolgreich erwies. Eine exakte Klassifizierung von TFCC-Läsionen ermöglicht die Wahl des für die jeweilige Läsion adäquaten Therapieverfahrens.

History of Wrist Arthroscopy

Wrist arthroscopy has a rich history, drawing on contributions from around the world. Its foundation was laid in Japan with Kenji Takagi and Masaki Watanabe, who developed the arthroscope and the techniques for arthroscopy. Across several decades they advanced the optic and lighting technology, allowing the miniaturization which made wrist arthroscopy technologically feasible. A safe and standardized technique for wrist arthroscopy was evolved by Terry Whipple, Gary Poehling, and James Roth in the 1980s, and they shared this with their fellow surgeons through courses and publications. The techniques then spread across the world, leading to widespread uptake and exploration of new therapeutic possibilities. The worldwide spread of wrist arthroscopy was accelerated by the European Wrist Arthroscopy Society (EWAS), founded in 2005 by Christophe Mathoulin. The Asia Pacific Wrist Association (APWA), founded by PC Ho in 2015, also extended the progression of wrist arthroscopy. This article brings together this history and tells the global story of its development through the recollections of those involved. The manuscript includes some amazing videos of the early historical arthroscopy. There are also videos of Gary and Terry describing some of their special memories of the early politics, developments, and evolution of wrist arthroscopy.

Ulnocarpal Impaction

Ulnocarpal impaction syndrome is a common cause for ulnarsided wrist pain caused by an abutment between the ulnar head and the lunotriquetral complex. This pain is typically triggered by load bearing and rotation of the forearm. Radiographic examination is often associated with positive ulnar variance and cysts in the lunate, edema of the ulnoproximal lunate is shown in MRI. Operative treatment aims to reduce load on the lunate, either by open ulnar shortening osteotomy or arthroscopic wafer procedure.

Ulnar shortening osteotomy as a treatment of symptomatic ulnar impaction syndrome after malunited distal radius fractures

A malunited distal radius fracture can lead to symptomatic ulnar impaction syndrome, which is a common cause for ulnar-sided wrist pain. If conservative treatment fails and symptoms persist after an arthroscopic ulnocarpal debridement, ulnar shortening osteotomy (USO) is the treatment of choice. Since the first USO described by Milch in 1941 after a malunited Colles fracture, many techniques have been described varying in surgical approach, type of osteotomy and osteosynthesis material used. Many studies demonstrated good to very good functional results after USO, reporting, however, a delayed union or non-union rate up to 18%. A modern, low profile, locking plate showed in our short-term study very good functional results and no implant-associated complications, in particular no non-union.

Arthroscopic Wafer Procedure Versus Ulnar Shortening Osteotomy as a Surgical Treatment for Idiopathic Ulnar Impaction Syndrome

PURPOSE

To compare clinical and radiologic outcomes and complication rates of the arthroscopic wafer procedure (AWP) and ulnar shortening osteotomy (USO) for idiopathic ulnar impaction syndrome (UIS).

METHODS

From May 2009 to June 2014, 42 patients who were aged 45 years or older with idiopathic UIS underwent either the AWP or USO under the following identical surgical indications: (1) less than 4 mm of positive ulnar variance, (2) Palmer classification 2C or 2D lesion of the triangular fibrocartilage complex, (3) stable distal radioulnar joint (DRUJ) and/or lunotriquetral joint, and (4) no evidence of osteoarthritis of the DRUJ or ulnocarpal joint. The patient assignment was not randomized. Were used a visual analog scale for ulnar wrist pain; grip strength; range of motion; the Mayo Wrist Score (MWS); and the Disabilities of the Arm, Shoulder and Hand (DASH) score at 3, 6, 12, and 24 months after surgery to compare clinical outcomes. Ulnar variance, cystic changes of the lunate and triquetrum, and DRUJ arthritis on radiographs and operation-related complications were compared.

RESULTS

This study evaluated 19 patients after the AWP and 23 patients after USO. At 3 months, the AWP produced significantly better outcomes than USO regarding grip strength (79.6% ± 14.3% vs 62.7% ± 12.6%, P < .001), MWS (81.8 ± 7.9 points vs 71.3 ± 14.2 points, P = .005), and DASH score (19.4 ± 8.4 vs 31.5 ± 14.0, P = .001); clinical outcomes were similar at 6, 12, and 24 months. The complication rates were 34.8% for USO and 10.5% for the AWP; complications included DRUJ arthritis (n = 4), implant irritation (n = 6), and refracture after implant removal (n = 2) in the USO group and secondary surgery (n = 1) and tendinopathy (n = 1) in the AWP group.

CONCLUSIONS

The AWP and USO for idiopathic UIS with subtle positive ulnar variance achieved similar clinical and radiologic outcomes at 2 years after surgery. However, compared with USO, the AWP showed lower complication rates and better grip strength, MWS values, and DASH scores at 3 months after surgery.

LEVEL OF EVIDENCE

Level III, comparative trial.

Arthroscopic Management of Ulnocarpal Impaction Syndrome and Ulnar Styloid Impaction Syndrome

Both ulnocarpal impaction syndrome and ulnar styloid impaction syndrome can produce ulnar wrist pain. The definition and clinical differentiation are explained. The relevant anatomy, biomechanics, causes, diagnosis, and arthroscopic treatments, as well as the surgical indications, techniques, and outcomes of these syndromes are discussed in detail.

The Oblique Metaphyseal Shortening Osteotomy of the Distal Ulna: Surgical Technique and Results of Ten Patients

Background Ulnocarpal abutment is a common condition following distal radius fractures. There are different surgical methods of treatment for this pathology: open and arthroscopic wafer procedure or an ulnar shortening osteotomy. We describe an oblique metaphyseal shortening osteotomy of the distal ulna using two cannulated headless compression screws. We report the results of 10 patients treated with this method. Materials and Methods Out of 17 patients, 10 could be reviewed retrospectively for this study. Patient-rated outcomes were measured using the VAS (visual analogue scale) for pain, PRWHE (patient-rated wrist and hand evaluation) survey, and Quick-DASH (disability of arm, shoulder and hand) survey for functional outcomes. At the review we measured the range of motion (ROM) of the wrist (extension and flexion, ulnar and radial deviation, pronation and supination). Grip strength, pronation, and supination strength of the forearm was measured using a calibrated hydraulic dynamometer. ROM and strength of the affected wrist was compared with ROM and strength of the unaffected wrist. Surgical Procedure Oblique long metaphyseal osteotomy of the distal ulna (from proximal-ulnar to distal-radial), fixed with two cannulated headless compression screws. Results The average postoperative VAS score for pain was 23.71 (standard deviation [SD] of 30.41). The average postoperative PRWHE score was 32.55 (SD of 26.28). The average postoperative Quick-DASH score was 28.65 (SD of 27.21). The majority of patients had a comparable ROM and strength between the operated side and the non-operated side. Conclusion This surgical technique has the advantage of reducing the amount of hardware and to decrease the potential hinder caused by it on medium term. Moreover, the incision remains smaller, and the anatomic metaphyseal localization of the osteotomy potentially allows a better and rapid healing.

Relationship Between Ulnar Variance, Cortical Bone Density, and Load to Failure in the Distal Radius at the Typical Site of Fracture Initiation

PURPOSE

Increased ulnar variance has been shown to lead to diminished load borne by the distal radius. The purpose of this study was to determine the correlations among ulnar variance, bone mineral density, and load to failure at the distal radius.

METHODS

Posteroanterior radiographs and computed tomographic scans were taken of 12 cadaveric forearms in neutral rotation. Ulnar variance was measured for each wrist by the method of perpendiculars. Measurements of cortical, trabecular, and combined bone density were made at the distal radius. We performed linear regression analysis and correlation analysis to determine the relationship between bone densities and ulnar variance measurements. Next, we loaded the 12 cadaveric radii to failure under axial compression. Linear regression analysis and correlation analysis were then performed to determine the relationship between load to failure and both ulnar variance and cortical density.

RESULTS

Increased ulnar variance was significantly correlated with decreased cortical bone density at the distal radius and both were correlated with decreased load to failure. We found no correlation between ulnar variance and trabecular density or combined trabecular and cortical bone density at the distal radius.

CONCLUSIONS

Our study found that increased ulnar variance and decreased cortical bone mineral density correlates with decreased load to failure under axial compression.

CLINICAL RELEVANCE

Ulnar variance is linked to both bone quality and load to failure at the distal radius.

Influence of Plate Size and Design upon Healing of Ulna-Shortening Osteotomies

Purpose Ulna-shortening osteotomy is one of the most established and most frequent operations in hand surgery. However, bone union is not always achieved and the use of plates implies potential risks and problems. The traditional points of criticism are the duration of bone healing, the incidence of nonunion, and the necessity of hardware removal due to the soft tissue irritation by the plate or the screws. These shortcomings have been addressed by an increasing standardization of the procedure and finally specific instruments and implants. The aim of this retrospective study was to compare a new LCP (locking compression plate) Ulna Osteotomy System 2.7 mm (Synthes, Paoli, PA) with the former 3.5-mm LCDCP (limited-contact dynamic compression plate) (Synthes) regarding consolidation, complications, and rate of plate removal. Methods To investigate the effect of an implant and technique specifically designed for this purpose, we have compared the course of healing and the result in 72 patients who have undergone ulnar shortening osteotomy using general instruments and applying a standard osteosynthesis plate (Synthes, 3.5-mm LCDCP) to a consecutive cohort of 40 patients who had ulnar shortening using the new dedicated ulna-shortening osteotomy system plate (Synthes, 2.7-mm LCP). Clinical and radiologic evaluation was performed 8 weeks, 3 months, 6 months, and 1 year postoperatively in all patients. Results The latter displayed shorter bone healing time, suggesting an advantage of an oblique osteotomy. There was no significant difference in rate of plate removal. Ultimate complication and consolidation rate was not different. Conclusion Using the new LCP 2.7 implant, time to consolidation was shorter and oblique osteotomies healed faster than transverse ones. However, in spite of the smaller plate, screws, and tapered design, the plate did not cause less local problems and failed to decrease the necessity of plate removal. Furthermore, the cost of the implant is higher than the LCDPC 3.5. Type of Study Retrospective comparative study. Therapeutic evidence Level III.

Wafer Resection of the Distal Ulna

The wafer procedure is an effective treatment for ulnar impaction syndrome, which decompresses the ulnocarpal junction through a limited open or arthroscopic approach. In comparison with other common decompressive procedures, the wafer procedure does not require bone healing or internal fixation and also provides excellent exposure of the proximal surface of the triangular fibrocartilage complex. Results of the wafer procedure have been good and few complications have been reported.

Ulnar shortening osteotomy for ulnar impaction syndrome

Background Ulnar impaction syndrome is a condition in which the ulna impacts on the ulnar carpus. This most commonly occurs when the ulna is longer than the radius, but it can also occur in wrists with ulnar neutral and ulnar negative variance. Materials and Methods In this paper we outline our surgical technique for ulnar shortening osteotomy. A previously published retrospective case series of 28 patients treated at our center is presented. Fifty consecutive patients who underwent ulnar shortening osteotomy (USO) for ulnar impaction syndrome were approached for study, and 28 consented to review. Mean preoperative ulnar variance was +2.3 mm, and mean postoperative ulnar variance was -0.8 mm. Mean follow-up time was 21.2 months (8 to 41 months) and ten of 28 were receiving workers' compensation. Mean preoperative pain score (visual analog scale; VAS) was 7.9. Univariate analysis was performed to assess clinical and demographic data. In addition, subgroup analysis of workers' compensation patients and smokers was performed. Description of Technique A longitudinal incision over the subcutaneous border of the ulna is used to expose the ulna between the distal and middle third of the ulna from the ulna styloid. Preoperative posteroanterior (PA) X-rays are reviewed to determine the amount of shortening required, with a goal of creating -2 mm variance postoperatively. A 6-hole dynamic compression plate is predrilled distally prior to performing two oblique osteotomies separated by the desired shortening length. The fragments are reduced, controlling for rotation, and plated using compression. In some cases, a lag screw is employed across the oblique osteotomy site. Results Mean pain scores were significantly reduced postoperatively (VAS 7.9 versus 3.1, P < 0.0001). The mean Disabilities of the Arm, Shoulder, and Hand (DASH) score was 37.2 postoperatively. Flexion, extension, and supination were reduced compared with the contralateral unaffected extremity (84.6%, 85.3%, and 86.9% of normal). Patients receiving workers' compensation and smokers had significantly more pain postoperatively (VAS 5.2 vs. 2.0, P = 0.0002 and VAS 4.4 vs 2.4, P < 0.05, respectively). Eleven of 28 patients required hardware removal for plate irritation, and five of 28 patients had a nonunion. Conclusion We present our surgical technique for ulnar shortening osteotomy. Pain was significantly improved in our population; however, patients receiving workers' compensation and smokers had less improvement in pain and higher disability scores.

Arthroscopic distal metaphyseal ulnar shortening osteotomy for ulnar impaction syndrome: a different technique

Ulnar impaction syndrome generally occurs with positive ulnar variance. The solution to the problem is to unload the ulnocarpal joint. Effective surgical options include diaphyseal ulnar shortening osteotomy, open wafer osteotomy, and arthroscopic wafer osteotomy. Recently, Slade and Gillon described an open procedure of ulnar shortening in the osteochondral region of the ulnar head. The procedure minimizes the risk of hemarthrosis and does not require hardware removal, which are problems with other surgical options. This article introduces a new arthroscopic technique of distal metaphyseal ulnar shortening osteotomy for ulnar impaction syndrome. This technique offers the advantages of minimizing surgical injury to the dorsal capsule of the distal radoulnar joint and so protects its stability.

Biomechanical analysis of the distal metaphyseal ulnar shortening osteotomy

PURPOSE

To investigate the effect of a closing wedge osteotomy at the distal ulnar metaphysis on unloading the ulnar side of the wrist.

METHODS

Seven fresh frozen cadaver arms mounted in a wrist simulator were used for the analysis. A 6-degrees-of-freedom load cell was mounted on the distal radius and another on the distal ulna. Radioulnar carpal joint forces and transverse distal radioulnar joint (DRUJ) load were measured at static wrist positions and during dynamic wrist motions before and after the distal metaphyseal ulnar shortening osteotomy (DMUSO) was performed.

RESULTS

At each static position, significant decreases in ulnar load were noted after DMUSO. In addition, mean and maximum loads decreased for each dynamic wrist motion. There were no statistically significant differences in transverse forces across the DRUJ after DMUSO.

CONCLUSION

This study showed that DMUSO is an effective way to decrease the load across the ulnocarpal joint. The geometry of the osteotomy and resultant change in the position of the ulnar head did not increase transverse joint reaction forces.

CLINICAL RELEVANCE

This technique is an alternative to open diaphyseal techniques or methods that damage the articular surface of the distal ulna. Clinical studies will be necessary to associate the biomechanical correction noted in this study with clinical symptom improvement.

Distal metaphyseal ulnar-shortening osteotomy: surgical technique

Ulnar impaction is a common condition encountered by hand surgeons. Historically, treatment of this condition has been with wafer resection of the distal ulna, by either open or arthroscopic means, or diaphyseal ulnar shortening osteotomy; however, both of these have the potential for prolonged recovery or a need for additional procedures. Wafer procedures, whether done by open or arthroscopic techniques, can result in hemarthrosis, and diaphyseal osteotomies can require hardware removal. Recently, Slade and Gillon described a technique of ulnar shortening in the osteochondral region of the ulnar head, which offers advantages over previously used techniques. The purpose of this manuscript is to describe this technique, as well as pearls and pitfalls associated with the procedure. To more accurately describe the location of the osteotomy, we have changed the name of the procedure from Dr. Slade's original description to distal metaphyseal ulnar-shortening osteotomy.

Ulnar impaction

Ulnar impaction syndrome is a common source of ulnar-sided wrist pain. It is a degenerative condition that occurs secondary to excessive load across the ulnocarpal joint, resulting in a spectrum of pathologic changes and symptoms. It may occur in any wrist but is usually associated with positive ulnar variance, whether congenital or acquired. The diagnosis of ulnar impaction syndrome is made by clinical examination and is supported by radiographic studies. Surgery is indicated if nonoperative treatment fails. Although a number of alternatives exist, the 2 primary surgical options are ulnar-shortening osteotomy or partial resection of the distal dome of the ulna (wafer procedure). This article discusses the etiology of ulnar impaction syndrome, and its diagnosis and treatment.

Arthroscopic wafer resection for ulnar impaction syndrome: prediction of outcomes

Twenty-six patients with mean age of 38.5 (range 18-59), from 1998 to 2005, with ulnar impaction syndrome who failed nonoperative treatments were included in our study. Patients' age, history of previous wrist fracture, presence of MRI signs and ulnar variance were recorded as variables. Also, patients' postoperative strength (compared to the contralateral wrist) and pain relief were collected as outcome measurements. Twenty-two patients (84.6%) had either good or excellent pain relief (median 4, range 1-4). Significant correlation was found between MRI findings and postop pain relief (r = 0.53, p < or = 0.01). History of previous distal radius fractures was negatively correlated with pain relief (r = -0.50, p < or = 0.01). No correlation was found between postop strength and any of the variables. Presence of MRI signs of UIS is a predictor of good outcome in arthroscopic wafer resection.

Management of post-traumatic malunion of fractures of the distal radius

Distal radius malunions are a common cause of patient morbidity. This review of the literature surrounding distal radius malunion covers the demographics, pathologic anatomy, and indications for surgery, surgical techniques, and salvage options. Particular emphasis is placed on subject areas that have not been reviewed as extensively in previous articles, including: intra-articular malunion, computer-assisted techniques, bone graft alternatives, and volar fixed-angle plate osteosynthesis.

Arthroscopic repair of Palmer 1B triangular fibrocartilage complex tears

PURPOSE

The objective of this retrospective study was to determine functional and subjective outcomes of patients with Palmer type 1B tears repaired arthroscopically and to investigate whether clinical outcomes are related to ulna length.

METHODS

Forty-six patients with arthroscopic repair of Palmer type 1B tears were reviewed. There were 23 males and 23 females. The average age was 34 years (range, 10 to 58 yrs). The average follow-up was 11 months (range, 6 to 23 mos), and the delay to surgery was 9.7 months. All patients suffered ulnar-sided wrist pain and were diagnosed with Palmer type 1B tears. The tear was repaired arthroscopically with an inside-outside suture technique. The range of motion (ROM), grip strength, pain, wrist score (modified Mayo wrist score), Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH) score, and ulna length (static and dynamic) were evaluated.

RESULTS

There was a reduction in pain and an improvement in grip strength. Postoperative ROM averaged 128 degrees +/- 23 degrees for the extension/flexion arc, 41 degrees +/- 11 degrees for the radial/ulnar deviation arc, and 171 degrees +/- 19 degrees for the pronation/supination arc of motion. However, no relation could be found between ulna length and clinical outcome. The modified Mayo wrist score was rated excellent in 22% of patients, good in 41%, fair in 27%, and poor in 10%. The average DASH score was 21.70 +/- 17.17 (range, 0 to 58.33).

CONCLUSIONS

Arthroscopic repair of Palmer type 1B tears yields satisfactory results. Sixty-three percent of patients achieved good to excellent results, experienced increased ROM, grip strength, and pain relief. Ulnar neutral or positive variance is not a contraindication for suture repair and does not require simultaneous ulna shortening when repairing the triangular fibrocartilage complex arthroscopically. A delay to surgery did not affect clinical outcome.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Wrist arthroscopy: current concepts

Wrist arthroscopy has steadily grown from a mostly diagnostic tool to a valuable adjunctive procedure in the treatment of myriad wrist disorders. The number of conditions that are amenable to arthroscopic treatment continues to grow. A detailed knowledge of the topographical and intracarpal anatomy, however, is essential to minimize complications and maximize the benefits. Although wrist arthroscopy can identify an anatomic abnormality, it cannot be used to differentiate between an asymptomatic degenerative condition versus a pathologic lesion that is the cause of wrist pain. A thorough wrist examination is still integral to any arthroscopic assessment. This article focuses on the methodology behind a normal arthroscopic wrist examination and discusses some of the more standard arthroscopic procedures along with the expected outcomes.

New advances in wrist arthroscopy

Wrist arthroscopy is a commonly used procedure that has undergone many modifications and improvements since it was first described. The advent of new portals (both dorsal and volar) means that the wrist joint can be viewed from virtually any perspective ("box concept"). Indications for wrist arthroscopy have continued to expand and include diagnostic and reparative procedures and, more recently, reconstructive, soft-tissue, and bony procedures. Arthroscopic grading of Kienböck's disease better describes articular damage compared with plain radiographs and can help guide surgical treatment options. Triangular fibrocartilage complex injury diagnosis, classification, and treatment can be performed arthroscopically, including distal ulna resection (wafer procedure). Assessment of fracture reduction of the distal radius and scaphoid is superior to that obtained with fluoroscopy, with the advantage of being able to look for associated soft-tissue and chondral injuries. Arthroscopic assessment of intercarpal ligament injuries and instability is now considered the gold standard by many authors. Arthroscopy can also aid us in the management of post-traumatic capsular contraction, resection of ganglia, and the relatively rare isolated ulna styloid impaction. Complications of wrist arthroscopy are relatively uncommon. With the ever-expanding list of indications and procedures that can be performed with this technique, it exists as an essential diagnostic and therapeutic tool for the orthopaedic surgeon.

Cartilage-retaining wafer resection osteotomy of the distal ulna

Ulnar-sided wrist pain resulting from ulnar impaction is common. We describe a new cartilage-retaining wafer resection osteotomy designed to keep the cartilage intact and decompress the ulnocarpal articulation without requiring internal fixation. We retrospectively reviewed seven patients with ulnar impaction who had the procedure. The minimum followup was 14 months (mean, 30 months; range, 14-38 months). The mean change in ulnar variance was -1.29 mm. Patients showed radiographic healing by a mean of 11 weeks. Our preliminary results suggest the cartilage-retaining wafer resection osteotomy may be an effective way to unload the ulnocarpal joint without requiring internal fixation or destruction of the distal ulna cartilage.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

The pathology of the long ulna: anatomy and treatment

A long ulna, as a result of congenital differential growth, such as Madelung's disease, or injury, commonly a consequence of a malunited distal radial fracture, may present clinically as pain, decreased motion, mainly of pronosupination, and weakness of grip. Secondary effects may include perforations and tears of the triangular fibrocartilage complex, cartilage wear of the proximal surface of lunate and triquetrum and tears of the lunotriquetral ligament. Positive ulnar variance may be evident on X-rays but a prominent ulnar head cannot always be excluded when there is neutral ulnar variance and further investigations, such as an arthroCTscan or arthroscopy, may be necessary. The two principle treatment options are (a) resection of the distal ulna (Darrach's and Sauvé-Kapandji's techniques are commonly used) and (b) techniques preserving the ulnar head, including different modalities of shortening osteotomy. The aim is to regain a congruent distal radioulnar joint, restore painless and normal pronosupination and prevent onset of osteoarthritis of this joint.

All-inside suture technique for Palmer class 1B triangular fibrocartilage repair

After completion of the diagnostic procedure, the ulnar-sided tear is identified and tear debridement is performed. A 1.5-cm incision is made to isolate the sensory branch of the ulnar nerve. This is made in the region of the 6U portal. The arthroscope is left in the 3-4 portal, and the slotted needle is inserted through the capsule wall, avoiding the isolated sensory ulnar branch, penetrating the ulnar-sided tear of the triangular fibrocartilage complex. A No. 2 PDS monofilament suture (Ethicon, Somerville, NJ) is inserted into the needle and visualized in the joint. The end of the suture is pulled through the 6R portal. The slotted needle is then removed and detached from the suture. The same needle is inserted through the tear about 0.3 cm from the point where the needle exited on the previous suture. The other end of the suture is inserted into the needle, and once visualized within the joint, it is withdrawn again through the 6R portal. In this way, we create an extra-articular loop with both ends of the same suture passing through the tear by way of the 6R portal. A knot is then tied and fixed inside the joint on the ulnar side of the triangular fibrocartilage complex. By use of the same technique, 2 or 3 more stitches can be placed, improving tear security.

Osteoarthritis of the wrist

Osteoarthritis of the wrist is one of the most common conditions encountered by hand surgeons. It may result from a nonunited or malunited fracture of the scaphoid or distal radius; disruption of the intercarpal, radiocarpal, radioulnar, or ulnocarpal ligaments; avascular necrosis of the carpus; or a developmental abnormality. Whatever the cause, subsequent abnormal joint loading produces a spectrum of symptoms, from mild swelling to considerable pain and limitations of motion as the involved joints degenerate. A meticulous clinical and radiographic evaluation is required so that the pain-generating articulation(s) can be identified and eliminated. This article reviews common causes of wrist osteoarthritis and their surgical treatment alternatives.

Management of post-traumatic malunion of fractures of the distal radius

Distal radius malunions are a common cause of patient morbidity. This review of the literature surrounding distal radius malunion covers the demographics, pathologic anatomy, and indications for surgery, surgical techniques, and salvage options. Particular emphasis is placed on subject areas that have not been reviewed as extensively in previous articles, including: intra-articular malunion, computer-assisted techniques, bone graft alternatives, and volar fixed-angle plate osteosynthesis.

Osteochondral shortening osteotomy for the treatment of ulnar impaction syndrome: a new technique

A new technique for ulna shortening is described. It is a modification of the open-wafer procedure that preserves the distal ulna's articular surface. A 4- to 5-mm chondral-cortical bone block is removed at the distal ulna articular-metaphysis junction. Closing the bone gap results in the osteotomy site proximal to the sigmoid notch. The distal ulna chondral-cortical fragment is secured with 1 or 2 headless compression screws, which permit early motion and results in solid healing. Similar to Feldon's previously described open-wafer procedure, this new technique reduces the ulna carpal load by reducing the distal ulna carpal length at the distal radioulnar joint. This new technique eliminates the exposure of the radiocarpal joint to continuous bleeding from the distal ulna's trabecular bone as seen in Feldon's open-wafer procedure and avoids all the inherent problems associated with plating the ulna for a typical distal ulna osteotomy, such as delayed union and painful hardware.

The effect of radial shortening on wrist joint mechanics in cadaver specimens with inherent differences in ulnar variance

PURPOSE

To assess load changes in the wrist and forearm resulting from surgically-induced radial shortening in wrists with inherent differences in ulnar variance.

METHODS

Eleven fresh cadaver upper extremities, 4 with ulnar-plus variance of 2 mm or greater and 7 with ulnar-minus variance of 2 mm or greater were used. The radius and ulna of each specimen were instrumented with load cells, a 15-mm segment of the radius was resected and replaced with aluminum blocks of various sizes, and the specimens were loaded with 143 N (32 lb) at 1-mm differences of radial length. The load distribution between the radius and ulna was measured.

RESULTS

The load distribution in the specimens with an ulnar-plus variance averaged 69% through the radius and 31% through the ulna. In the wrists with ulnar-minus variance, the load distribution averaged 94% through the radius and 6% through the ulna. The mean force in the ulna increased and the mean force in the radius decreased with incremental shortening of the distal end of the radius. The mean force through the ulna in the ulnar-plus-variance group was always higher than that of the ulnar-minus-variance group. When compared not by the number of millimeters of radial shortening but by the adjusted ulnar variance, there was no difference between the ulnar-plus-variance and the ulnar-minus-variance groups.

CONCLUSIONS

Wrists with ulnar-minus variance could accommodate radial shortening without as much increase in the ulna load as wrists with ulnar-plus variance. The clinical relevance is that a patient with an ulnar-minus variance may accommodate more radial shortening after a wrist fracture without developing an ulnar impaction syndrome than a patient with an ulnar-plus-variant wrist.

Traitement arthroscopique des conflits ulnolunaires

The ulnar impaction syndrome is due to hyperpressure in the ulnocarpal joint. It occurs most frequently following distal radial fractures with shortening, but can also be secondary to a primitive length discrepancy between a short radius and a long ulna (positive ulnar variance). Symptoms and clinical findings, even though characteristic, are not specific. Standard X rays show a positive ulnar variance, and sometimes a hyperpressure cyst in the lunate. CT arthroscan and MRI studies demonstrate indirect signs of hyperpressure. If medical treatment fails to improve the condition, the choice surgical technique is arthroscopic, allowing debridement of the TFCC central tear, and shortening of the horizontal aspect of the ulnar head.

Ulnar impaction syndrome

Although Palmer's classification of TFCC lesions differentiates post-traumatic central perforations (IA tears) from degenerative tears secondary to ulnocarpal impaction (IIC) [3], the distinction is not always clear clinically. In the final analysis, the literature suggests that as many as 25% of wrists with TFCC tears have residual symptoms following arthroscopic debridement alone [23], and it is likely that static or dynamic ul-nar positive variance plays a role [2,5,17,25]. The authors' results suggest that combined arthroscopic TFCC debridement and wafer resection are feasible and efficacious as treatment for all stages of ulnar impaction syndrome. When class II A and B changes are observed, that is, when a TFCC perforation has not yet developed, the authors have observed favorable results in most patients following arthroscopic TFCC central disc excision and wafer resection as an alternative to ulnar shortening osteotomy [33] or open wafer excision [10].

Effects of wafer resection and hemiresection from the distal ulna on load-sharing at the wrist: a cadaveric study

PURPOSE

Ulnar impaction syndrome is commonly the result of a naturally occurring ulnar-positive condition, distal radius fracture malunion, or collapse of a fractured radial head. The Feldon wafer procedure and the Bowers distal hemiresection procedure are designed to decrease force transmitted through the distal ulna. The purpose of this study was to measure the effects of these procedures on distal ulnar loading with varying degrees of ulnar positivity at the wrist.

METHODS

Using a specially designed miniature load cell distal ulnar force was measured in 20 fresh-frozen cadaveric forearms as the wrist was loaded axially to 134 N in neutral forearm rotation; tests were performed in valgus alignment with the elbow flexed to 90 degrees . Ulnar positivity (0 mm, +2 mm, +4 mm, and +6 mm) was created by incremental shortening of the distal radius using a sliding plate. The radial neck was sectioned transversely and the radial head fragment was fixed in its anatomic position using cemented metal prongs connected to a rigid bar; this allowed the radial head to be disconnected and tilted out of the loading pathway to simulate an excised radial head. Loading tests (with and without the radial head in place) were repeated after removal of a 3-mm wafer of bone beneath the triangular fibrocartilage complex, and again after a hemiresection of the distal ulna to the base of the ulnar styloid process.

RESULTS

For each ulnar status condition (intact, wafer removal, hemiresection) the mean distal ulnar force generally increased as the wrist became more ulnar positive. Both wafer removal and hemiresection significantly decreased mean distal ulnar forces under all conditions of ulnar variance, with or without the radial head in place. With the radial head in place the mean distal ulnar forces (expressed as a percentage of applied wrist force) for the 0-mm condition were 16.9% (intact), 3.8% (wafer removal), and 3.5% (hemiresection); corresponding values for the +6-mm condition were 61.6% (intact), and 39.8% (wafer removal), 15.1% (hemiresection). With the radial head removed the mean distal ulnar forces for the 0-mm condition were 31.7% (intact), 4.6% (wafer removal), and 4.4% (hemiresection); corresponding values for the +6-mm condition were 96.4% (intact), 71.6%, (wafer removal), and 27.2% (hemiresection). The decrease of distal ulnar force resulting from hemiresection was significantly greater than that for wafer removal for all ulnar-positive conditions; force reductions were not significantly different between the 2 procedures with neutral ulnar variance.

CONCLUSIONS

The results of the present study can help to offer a biomechanical basis for choosing between a Feldon wafer procedure and a Bowers hemiresection procedure in patients with ulnocarpal impaction syndrome. Both procedures produced equal decreases of distal ulnar force in the intact forearm. With an ulnar-positive wrist, the condition for which the procedure would be performed commonly, the hemiresection was more effective in decreasing force transmitted through the distal ulna.

[The arthroscopic "wafer procedure" in degenerative disc ulnocarpal tears with ulnocarpal compression syndrome. Techniques, indications, results]

The wafer procedure is a technique involving the partial resection of the distal ulna for the treatment of patients with symptomatic tears of the TFCC, for ulnar abutment syndrome or both. The TFCC-tears are classified as Palmer type 2. The wafer procedure can be performed as an open procedure or arthroscopically. It is an alternative to a shortening osteotomy of the ulna and decompresses the ulnocarpal joint. In ten cases with long-term follow-up, the preferability of the arthroscopic method is demonstrated: a minimally invasive technique, optimal assessment of all lesions, maximum protection of all uninjured structures in comparison to the open method, single stage procedure, and low complication rate. The long-term results are predominantly positive, so that the arthroscopic wafer procedure should be performed more often than it is today.

A comparison of combined arthroscopic triangular fibrocartilage complex debridement and arthroscopic wafer distal ulna resection versus arthroscopic triangular fibrocartilage complex debridement and ulnar shortening osteotomy for ulnocarpal abutment syndrome

PURPOSE

Treatment of ulnocarpal abutment (UAS) syndrome involves decompression of the pressure and impingement, or abutment of the ulnocarpal articulation. Debridement of triangular fibrocartilage complex (TFCC) tears alone in the patient with UAS may have a failure rate of as much as 25% to 30%. Ulnar shortening osteotomy (USO) can be an effective treatment of failed TFCC debridement. Good results have been reported with combined arthroscopic TFCC debridement and mechanical arthroscopic distal ulnar resection. Similar results have been reported with both ulnar shortening osteotomy and open wafer distal ulnar resections in the UAS patient. Because all of these treatment choices appear to yield similar relief of symptoms, determination of the optimal treatment protocol remains a point of debate. The purpose of this study was to evaluate 2 different surgical treatments for UAS.

TYPE OF STUDY

Retrospective review.

METHODS

Eleven combined arthroscopic TFCC debridement and arthroscopic distal ulna resections (arthroscopic wafer procedures; AWP) were compared with 16 arthroscopic TFCC debridement and USOs. All patients had diagnostic wrist arthroscopy and arthroscopic TFCC debridement. All patients presented with ulnar wrist pain or neutral or positive ulnar variance, and all experienced at least 3 months of failed conservative management.

RESULTS

At mean follow-up times of 21 and 15 months, respectively, 9 of 11 patients showed good to excellent results after arthroscopic TFCC debridement and AWP compared with 11 of 16 after arthroscopic TFCC debridement and USO. A statistically significant difference (P <.05) in the complication rates was identified, including secondary procedures and tendonitis. One secondary procedure and 2 cases of tendonitis were seen in the arthroscopic wafer group.

CONCLUSIONS

Combined arthroscopic TFCC debridement and arthroscopic wafer procedure provides similar pain relief and restoration of function with fewer secondary procedures and tendonitis when compared with arthroscopic TFCC debridement and USO, for the treatment of UAS.

LEVEL OF EVIDENCE

Level III.

Laser-assisted arthroscopic ulnar shortening

The purpose of this study is to evaluate arthroscopic ulnar shortening with the holmium:yttrium-aluminum-garnet (Ho:YAG) laser for the treatment of ulnocarpal abutment syndrome (UAS). This is a retrospective review of the experience of a single surgeon using this technique between 1994 and 2000. Unloading the ulnocarpal joint is the recognized treatment of UAS. Ulnar shortening via a diaphyseal osteotomy and plating (USO) has been used with good results; however, nearly 50% of patients will require hardware removal. Researchers have reported similar results between open distal ulnar resection (the wafer procedure) and USO for the treatment of UAS. Researchers have also reported similar results with mechanical arthroscopic distal ulnar resections (arthroscopic wafer distal ulnar resection [AWP]) for UAS. Eleven patients who underwent Ho:YAG laser-assisted arthroscopic distal ulnar resection were retrospectively evaluated. The average follow-up time was 31 months, with a range of 7 to 61 months. Evaluation using Darrow' s criteria revealed 64% excellent (7 of 11), 18% good (2 of 11), 9% fair (1 of 11), and 9% poor (1 of 11) results. The average return to work time was 4.7 months, with a range of 1.5 to 16 months. Complications included 1 repeat surgery for ulnocarpal scar formation, 2 cases of transient tendonitis, and 1 portal site erythema without drainage that was treated with antibiotics. One patient (the one with a poor result) has not returned to work for unrelated reasons. chi- square analysis (P <.05) was unable to identify a statistical difference between the reported results of arthroscopic wafer procedures, USOs, and open wafer procedures. We concluded that Ho:YAG laser-assisted arthroscopic ulna shortening procedures show similar results to those reported for arthroscopic wafer procedures, open wafer procedures, and USOs. Return to work times are similar to those reported by other researchers, as is the return to preoperative occupation rate. There is no need for late removal of hardware, as is sometimes associated with USO. Our experience has been that the Ho:YAG laser removes hyaline cartilage and subchondral bone rapidly and with little debris, and thus facilitates the ulna shortening procedure.

Combined arthroscopic TFCC debridement and wafer resection of the distal ulna in wrists with triangular fibrocartilage complex tears and positive ulnar variance

Because a certain percentage of patients with positive ulnar variance experience incomplete pain relief after triangular fibrocartilage complex (TFCC) debridement alone, we prospectively evaluated the feasibility and efficacy of combining arthroscopic TFCC debridement with arthroscopic wafer resection in such wrists as part of the same surgical procedure. We enrolled 12 patients between July 1998 and July 2000 and performed both subjective and objective assessment at follow-up with a minimum of 6 months and an average of 14 months. Seven posttraumatic and 5 degenerative tears were identified. Preoperative ulnar variance with a pronated grip x-ray averaged 2 mm and ranged between 1 and 4 mm. At final review 8 patients experienced complete pain relief and 4 experienced only minimal symptoms. The ulnocarpal stress test failed to elicit pain in any wrist. Nine patients were very satisfied, and 3 were satisfied. Grip strength improved 8 kg (36%). This procedure should be considered in the treatment of ulnar wrist pain when TFCC tears and positive ulnar variance coexist.

Arthroscopic repair of triangular fibrocartilage complex injuries

The triangular fibrocartilage complex is a functionally and anatomically intricate group of structures located at the ulnar aspect of the wrist. Injury to this structure affects the biomechanics of the wrist and makes functional restoration difficult. This article reviews the anatomy, biomechanics, diagnosis, and arthroscopic treatment of triangular fibrocartilage complex injuries.

Triangular fibrocartilage complex tears in the athlete

The treatment of triangular fibrocartilage tears in the athlete presents more of a rehabilitation challenge than a surgical technique challenge. The rehabilitation regimen is a function of the sport. Although injuries to the shoulder and knee can be career ending, injuries to the TFCC usually, but not always, can be treated successfully.

The ulno-carpal abutment syndrome. Follow-up of the wafer procedure

Seven wrists in six patients with ulno-carpal abutment syndrome were treated by a subchondral distal ulna resection (wafer procedure). The average follow-up was 36 months. Wrist function was evaluated using a clinical scoring chart. The parameters were pain, range of motion, grip strength and activities. One patient had a poor result, one a fair result and the remaining had good to excellent results. In all cases grip strength showed dramatic improvement. Complications were limited to palpable subcutaneous nylon sutures requiring removal in three patients and extensor carpi ulnaris tendinitis in one.

Wrist arthroscopy. Indications and clinical applications

We reviewed retrospectively a series of 128 consecutive patients who had wrist arthroscopy at our institution between January 1988 and July 1991. The aim of the procedure was to establish a diagnosis in 27 patients, to challenge a pre-operative diagnosis in 95 patients and to evaluate joint surfaces in six patients. For the 27 patients with a previously unknown diagnosis, the diagnostic sensitivity was 67% and the specificity 100%. Arthrotomy or other intervention was avoided in 18. For the 95 patients with an established pre-operative diagnosis, arthrotomy was avoided in 45: in 26 the desired procedure could be done arthroscopically, and in 19 the diagnosis, as improved by arthroscopy, was felt not to require further treatment. Procedures performed arthroscopically included débridement of triangular fibrocartilage and inter-carpal ligament tears; lysis of adhesions, and synovectomy. In six patients, arthroscopy was performed to evaluate joint surfaces after fracture reduction or before ulnar shortening osteotomy. In none of the six was arthrotomy felt necessary after arthroscopy. Wrist arthroscopy avoided the need for further surgery in 66 (52%) of our patients; arthrotomy was avoided in 69 (54%). In cases with significant carpal instability evident pre-operatively, arthroscopy was unlikely to avoid the need for open treatment.