Background  Dorsal intercalated segment instability (DISI) in scaphoid nonunions is frequently attributed to fracture location relative to ligamentous attachments onto the scaphoid apex. We hypothesize scaphoid length loss to have a stronger correlation with DISI deformity than fracture location in patients with scaphoid nonunion. Questions/Purposes  To investigate the correlation between (1) scaphoid length loss, (2) fracture location relative to the scaphoid apex, and (3) type of nonunion (Herbert classification) and DISI deformity in skeletally mature patients with scaphoid nonunion. Patients and Methods  Twenty-seven cases of computed tomography (CT)-confirmed scaphoid nonunion (>6 months) were retrospectively included. Our primary outcome was the degree of DISI as measured by the radiolunate (RL) angle on CT. Scaphoid length loss was expressed as height-to-length (H/L) ratio. Fracture location was classified as proximal or distal to the scaphoid apex. Nonunions were classified as fibrous unions (type D1) or pseudoarthrosis (type D2). The correlation between RL angle, H/L ratio, fracture location, and nonunion type was evaluated. Results  H/L ratio was the only factor associated with the degree of DISI as measured by RL angle. As scaphoid length loss increased (increasing H/L ratio), the RL angle increased. There was no significant difference in RL angle between fractures located proximal (30 degrees) or distal (28 degrees) to the scaphoid apex, or type D1 (31 degrees) versus type D2 (28 degrees) nonunions. There was no correlation between patient age, sex, or wrist side affected and RL angle. Conclusions  Scaphoid length loss, rather than fracture location, is correlated to the degree of DISI deformity in patients with scaphoid nonunion. This highlights the importance of restoring scaphoid height when planning scaphoid nonunion reconstruction. Level of Evidence  Level III, diagnostic study.

Background  Many debates are still ongoing for the management of chronic scapholunate (SL) injuries. We have proposed an arthroscopic technique of dorsal capsulodesis with good clinical results. We now propose a radiological follow-up. Purpose  To determine if arthroscopic dorsal capsulodesis can improve the radiographic SL angle and maintain this correction over time. Methods  From January 2020 to January 2021, we included every patient with an SL instability and sorted them according to the European Wrist Arthroscopy Society (EWAS) classification. All patients had bilateral X-rays with a measurement of the radiolunate (RL) and SL angles for both the pathologic and healthy side. We also included patients with lunotriquetral or triangular fibrocartilage complex lesions. The exclusion criteria were the presence of arthritis and persistent intraoperative SL instability after capsulodesis. An arthroscopic dorsal capsulodesis was performed in all patients as originally described by Mathoulin. The RL and SL angles were then again measured on the immediate postoperative X-ray, and then again at 3, 6, and 12 months postoperatively. The statistical analysis was done using a paired Student\'s t -test with 145 degrees of freedom and α = 0.05. Results  We included a total of 146 patients with a 1-year follow-up. Both the RL angle and the SL angles approach the healthy side at 12 months postoperatively. The RL angle has increased from -7.23 degrees to 4.37 degrees; the difference is still statistically significative, but it is almost equal to the healthy side (5.16 degrees). The SL angle has lowered from 74.55 to 54.95; the difference is still statistically and radiologically significative (6.788 degrees) but has been lowered by 74.3%. Conclusion  This study shows that this technique can normalize the dorsal intercalated segment instability (DISI) over time without the need for any pinning or invasive ligament reconstructive surgery. Level of Evidence  Level IV, cohort study. Clinical Relevance  Dorsal capsulodesis should be considered in all reducible SL injuries, even when DISI is present.

Scapholunate and lunotriquetral instability are common causes of chronic, debilitating wrist pain and functional impairment. In the setting of subacute or chronic injuries with predynamic or dynamic instability, the ideal surgical approach remains unclear. In January 2020 the authors started enrolling patients with predynamic and dynamic instability in an Institutional Review Board-approved prospective study, aimed at meticulously studying outcomes using the all-dorsal InternalBrace reconstruction technique. The all-dorsal technique described herein is straightforward, efficient, and easy to learn, with early outcomes equivalent or superior to those of other techniques.

Scapholunate instability (SLI) is the most common carpal instability described. SLI leads to a degenerative arthritic pattern known as scapholunate advanced collapse (SLAC). Diagnosis of SLI can be challenging in pre-dynamic and dynamic stages. CT arthrogram, MR arthrogram and dynamic fluoroscopy are helpful in diagnosis while arthroscopy remains the gold standard. SLI is a multi-ligament injury, which involves not only the scapholunate interosseous ligament (SLIL) but also the extrinsic carpal ligaments. Hence, it is better described as an injury compromising the \'dorsal scapholunate(dSLL) complex\'. A repair can be attempted for acute SLI presenting within 6 weeks of injury. Reconstruction is the mainstay of treatment for chronic SLI without degenerative changes. Multiple repair techniques have been described which include capsulodesis and tenodesis procedures. The clinical outcomes of the techniques have improved over the years. However, a common problem of all these techniques is the lack of long-term data on the outcomes and deteriorating radiological parameters over time. SLI staging is an important factor to be considered in choosing the reconstruction techniques for a better outcome. Currently, there is a trend towards more biological and less invasive techniques. Regardless of the technique, it is important to preserve the nerve supply of the dorsal capsuloligamentous structures of the wrist. Arthroscopic techniques being minimally invasive have the advantage of less collateral damage to the capsuloligamentous structures. Rehabilitation involves a team approach where a protected dart thrower\'s motion is allowed after a period of immobilization. Strengthening SL-friendly muscles and inhibiting SL-unfriendly muscles is a key principle in rehabilitation.

OBJECTIVE: Scaphoid non-union causes osteoarthritis but factors associated are poorly understood. We investigated the rate of osteoarthritis after scaphoid fracture non-union, and if duration and fracture location influenced arthritis and its severity.
METHODS: This retrospective cross-sectional observational study of 278 consecutive cases with scaphoid fracture non-union retrieved data on demographics, non-union duration, fracture location, dorsal intercalated segment instability (DISI), severity and distribution of wrist arthritis. Patient Evaluation Measure (PEM) and Quality of Life assessed impact on patients. Regression models investigated prediction of osteoarthritis by different variables. Time-to-event analysis investigated osteoarthritis evolution. Missing (MAR) data for the PEM and QoL was imputed and analysed.
RESULTS: 278 patients, 246 males, aged 27.9 years (range 11 to 78 years), with a scaphoid fracture non-union confirmed on computed tomography (CT) scans (243) and plain radiographs (35) were reviewed. The interval between injury and imaging was 3.3 years (SD 5.9 years; range 0.1-45). The fracture was proximal to the ridge in 162, distal to the ridge in 83 and in the proximal 20% in 33. DISI (RLA ≥ 10°) occurred in 93.5% (260/278). Osteoarthritis was identified in 62.2% (173/278), and we classified a SNAC pattern in 93.6% (162/173). Of these, 100 (61.7%) had SNAC 1, 22 (13.6%) SNAC 2, 17 (10.5%) SNAC 3, and 23 (14.2%) SNAC 4. The mean duration in years for SNAC 1, 2, 3 and 4 were 2.5, 6.0, 8.2, and 11.3 years respectively. In fractures proximal to the ridge, 50% had arthritis in 2.2 years. Whereas in proximal pole, and distal to the ridge, 50% developed in 3.8 and 6.6 years, respectively. The PEM score was 42.8% (SD 18.9%) in those without arthritis and 48.8% (SD 21.5%) in those with arthritis. The mean QoL was 0.838 in patients without SNAC and 0.792 with SNAC.
CONCLUSIONS: Scaphoid fracture non-union caused early carpal collapse, majority had osteoarthritis usually observed within a year following injury and occurred earliest in proximal waist fractures. Distribution of osteoarthritis (SNAC stage) may not always follow a distinctive pattern, as previously described.

Objective  This article compares predictors of failure for vascularized (VBG) and nonvascularized bone grafting (NVBG) of scaphoid nonunions. Methods  We conducted a systematic literature review of outcomes after VBG and NVBG of scaphoid nonunion. Fifty-one VBG studies ( N  = 1,419 patients) and 81 NVBG studies ( N  = 3,019 patients) met the inclusion criteria. Data were collected on surgical technique, type of fixation, time from injury to surgery, fracture location, abnormal carpal posture (humpback deformity and/or dorsal intercalated segmental instability [DISI]), radiographic parameters of carpal alignment, prior failed surgery, smoking status, and avascular necrosis (AVN) as defined by punctate bleeding, magnetic resonance imaging (MRI) with contrast, MRI without contrast, X-ray, and histology. Meta-analysis of proportions was conducted with Freeman-Tukey double arcsine transformation. Multilevel mixed-effects analyses were performed with univariable and multivariable Poisson regression to identify confounders and evaluate predictors of failure. Results  The pooled failure incidence effect size was comparable between VBG and NVBG (0.09 [95% confidence interval [CI] 0.05-0.13] and 0.08 [95% CI 0.06-0.11], respectively). Humpback deformity and/or DISI (incidence-rate radios [IRRs] 1.57, CI: 1.04-2.36) and lateral intrascaphoid angle (IRR 1.21, CI: 1.08-1.37) were significantly associated with an increased VBG failure incidence. Time from injury to surgery (IRR 1.09, CI: 1.06-1.12) and height-to-length (H/L) ratio (IRR 53.98, CI: 1.16-2,504.24) were significantly associated with an increased NVBG failure incidence, though H/L ratio demonstrated a wide CI. Decreased proximal fragment contrast uptake on MRI was a statistically significant predictor of increased failure incidence for both VBG (IRR 2.03 CI: 1.13-3.66) and NVBG (IRR 1.39, CI: 1.16-1.66). Punctate bleeding or radiographic AVN, scapholunate angle, radiolunate angle, and prior failed surgery were not associated with failure incidence for either bone graft type ( p > 0.05). Conclusion  Humpback deformity and/or DISI and increasing lateral intrascaphoid angle may be predictors of VBG failure. Time from injury to surgery may be a predictor of NVBG failure. AVN as defined by decreased contrast uptake on MRI may be a marker of increased failure risk for both bone graft types.

We compared two methods of fixation for unstable scaphoid waist nonunions regarding rate of scaphoid union, union time, deformity correction, clinical outcomes (pain, range of motion, and grip strength), and QuickDASH scores. Eighty-nine patients who undergo cancellous iliac bone grafting and internal fixation either with a Herbert screw (n = 46) or multiple Kirschner wires (n = 43) were evaluated. The rate of scaphoid union in the K-wire group was 98% (n = 42) versus 89% (n = 41) in the screw group. The mean union time and duration of surgery for K-wire group versus screw group were 12 versus 15 weeks and 45 versus 66 min respectively. There was no significant difference between the two groups with respect to deformity correction, clinical outcomes, and QuickDASH scores. Despite there was no significant difference in the rate of scaphoid union between the two fixation methods, the K-wires procedure had the advantages of short union time, less demanding, and less expensive than the screw implant.

The study compared the impact of the Kirschner wires versus Herbert screw fixation on the rate of union, time to union, correction of deformity, and clinical outcome in adults with unstable scaphoid waist fracture nonunions without avascular necrosis.
We prospectively randomized 122 patients to undergo corticocancellous iliac bone grafting and internal fixation either with multiple Kirschner wires or Herbert screw. Radiographs, clinical outcome measures (pain, range of motion, and grip strength), and the Quick DASH score were taken pre- and post-operatively.
The rate of the scaphoid union in the Kirschner wire group was 91% versus 88% in the Herbert group. No difference was detected between the two groups with respect to the time to union, deformity correction, pain analysis, range of motion, grip strength, return to work, and complications.
Using of multiple Kirschner wires as a fixation method for unstable scaphoid waist fracture nonunion that was treated by open reduction and corticocancellous iliac bone grafting had a shorter operative time and lower cost as compared with the Herbert screw fixation. Herbert screw fixation was technically more demanding in terms of technique than K-wires. However, because of easy application of Kirschner wires, and low cost, especially in developing countries, it may be a good alternative to Herbert screw.

Background: The scaphoid-trapezoid-trapezium (STT) articulation stabilizes the scaphoid and links the proximal and distal carpal rows. The purpose of the study was to determine whether trapezium excision in the treatment of trapeziometacarpal (TM) arthritis affects carpal stability. Methods: A retrospective chart and radiographic review was performed on all wrists that underwent trapeziectomy with suspensionplasty or ligament reconstruction, and tendon interposition for TM arthritis between 2004 and 2016. Radiographic outcome measures included the modified carpal height ratio (MCHR) and radioscaphoid (RS), radiolunate (RL), and scapholunate (SL) angles. Degenerative change at the TM and STT joints was classified according to the Eaton-Littler, and Knirk and Jupiter classification systems. Radiographic parameters were compared between preoperative and final follow-up time points. Results: A total of 122 wrists were included in the study with a mean follow-up of 3.5 years (range: 1.0-13.0 years). The mean RL (range: -2.2° ± 11.8° to -10.7° ± 16.5°) and RS angles (range: 52.6° ± 13.8° to 44.4° ± 17.8°) decreased significantly (<.001) without significant change in SL angle, indicating progressive lunate and scaphoid extension after trapeziectomy. The mean MCHR decreased significantly (range: 1.6 ± 0.1 to 1.5 ± 0.1) following trapeziectomy, indicating progressive carpal collapse. Progressive scaphoid-trapezoid arthrosis was observed following trapeziectomy. No other preoperative radiographic factors investigated were associated with significant differences in preoperative and postoperative values for radiographic outcome measures. Conclusions: Trapeziectomy can lead to loss of carpal height, coordinated extension of both the lunate and scaphoid, and progressive scaphotrapezoid arthrosis. As such, in wrists with dynamic or static carpal instability, trapeziectomy should be performed with caution due to the risk of carpal collapse with a nondissociative pattern of dorsal intercalated segment instability.

Progression to dorsal extension of the lunate after distal scaphoidectomy was described more than a decade ago. Still, this technique remains a popular choice for surgical treatment of isolated scaphotrapeziotrapezoid osteoarthritis (STT OA). This study aimed to investigate short-term postoperative function, patient satisfaction and radiographic outcomes of distal scaphoidectomy with tendon interposition for isolated STT OA in the wrist. Scaphoid resection width, amount of DISI and postoperative complications were also assessed. We evaluated all distal scaphoidectomies done at our hospital from 2012 to 2018. Postoperative clinical analysis consisted of grip and key pinch strength, joint amplitude, pain on visual analog scale (VAS), hand usability (VAS) and functional scores (QuickDASH and PRWHE scores). On follow-up radiographs, we measured the amount of DISI, resection height and scaphoid working length and compared them to functional scores. Eighteen patients with 21 operated wrists were eligible. Average time to postoperative evaluation was 36 (5-78) months. We observed DISI in 95% of the cases (n=19). A mean increase of 13° (±6) in radiolunate angle was noted when comparing pre- and postoperative radiographs. Neither the amount of DISI nor the resection height was significantly correlated with the functional scores. No revision surgery for advanced wrist collapse was reported. Four concomitant surgeries were needed. Distal scaphoid excision with tendon interposition yields good short-term results in isolated STT OA. While 95% of cases developed a DISI deformity, there were no cases of functional impairment. Longitudinal studies with long-term follow-up are required to further evaluate lunate extension and possible clinical implications.