Patient Perspectives on Cognitive Behavioral Therapy for Thumb, Hand, or Wrist Pain and Function: A Survey of 98 Patients.

PURPOSE: Cognitive behavioral therapy (CBT) is an established option to improve pain and function for many orthopedic conditions. Our purpose was to obtain patient perspectives regarding CBT for thumb, hand, or wrist pain and function. METHODS: Between March and April 2022, we distributed an electronic survey via email to patients in our institution's health system with a diagnosis of arthritic or non-specific thumb, hand, or wrist pain. The survey included the opening statement "Cognitive Behavioral Therapy (CBT) is a non-medication option to help manage pain and improve function" and up to 13 questions pertaining to patients' experiences and perceptions regarding CBT. The survey was anonymous and did not collect protected health information. We used descriptive statistics for the findings. RESULTS: We distributed the survey to 327 patients, yielding a 30% response rate (98/327). Of the respondents, 17 reported already using CBT to specifically help with pain/function. Of these, 15 felt it was helpful and agreed it could help others. Of the subset that used CBT for arthritis, all felt it was helpful. Of the 75 respondents with no CBT experience, 42 indicated "I've never heard of it," 28 responded "I never had it recommended as an option," and 16 marked "I don't know enough about it." Small subsets noted potential personal barriers to CBT implementation, such as cost, time involved, or perceived lack of potential efficacy for themselves. CONCLUSIONS: A small proportion of patients from our institution with thumb, hand, or wrist pain are utilizing CBT, and the majority finds it helpful. CLINICAL RELEVANCE: While some patients are already substantially benefiting from CBT to improve their thumb, hand, or wrist pain or function, there is a notable opportunity for providers to increase awareness and recommendations for this option.

Comparison of 3 Dynamic External Fixation Devices for Proximal Interphalangeal Joint Dorsal Fracture-Dislocations in a Cadaver Model.

PURPOSE: Several improvised dynamic external fixation devices are used for treating unstable dorsal proximal interphalangeal (PIP) joint fracture-dislocations. We compared the effectiveness of 3 constructs for simulated dorsal PIP joint fracture-dislocations in a cadaver model. METHODS: We tested 30 digits from 10 fresh-frozen, thawed cadaver hands. We aimed to remove the palmar 50% of the base of each digit's middle phalanx (P2), simulating an unstable dorsal PIP joint fracture-dislocation. Each PIP joint was then stabilized via external fixation with either a pins-and-rubber-bands construct, pins-only construct, or tuberculin syringe-pins construct. We allocated 10 digits per fixation group. The finger tendons were secured to a computer-controlled stepper motor-driven linear actuator. Via this mechanism, all PIP joints were taken through 1,400 cycles of flexion-extension. With the PIP joint in neutral extension, we measured the P2 dorsal translation at baseline, after fixator stabilization, and after the motion protocol. RESULTS: The actual mean P2 palmar defect created was 48% of the base. All PIP joints were unstable after creating the defect, with a mean initial P2 dorsal displacement of 3.7 mm. After application of the fixators, all PIP joint dislocations were reduced. The median residual P2 dorsal displacements were 0.0 mm for the pins-rubber bands group, 0.1 mm for the pins-only group, and 0.5 mm for the syringe-pins group. There were no cases of PIP joint redislocation after flexion-extension cycling, and the median dorsal P2 displacements were 0.0 mm for the pins-rubber bands group; 0.0 mm for the pins-only group; and 0.5 mm for the syringe-pins group. CONCLUSIONS: All 3 external fixators restored PIP joint stability following simulated dorsal fracture-dislocation, with all reductions maintained after motion testing. The syringe-pins construct had significantly greater median residual P2 dorsal displacement after the initial reduction and motion testing, which is of unclear clinical importance. CLINICAL RELEVANCE: This study informs surgeon decision-making when considering dynamic external fixator options for dorsal PIP joint fracture-dislocations.

All-Suture Anchor Repair of the Flexor Digitorum Profundus Insertion: A Biomechanical Comparison of 2 Suturing Techniques.

PURPOSE: We compared 2 suturing techniques for reattachment of the flexor digitorum profundus (FDP) via all-suture anchor. METHODS: We used fresh, matched-pair, cadaveric hands. We disarticulated the fingers at the proximal interphalangeal joints, preserving the proximal FDP. We released the FDPs at their distal insertion and placed an all-suture, 1.0-mm anchor at the center of each FDP footprint. Each anchor's sutures were used to reattach each FDP using 1 of 2 techniques: group H (n = 14) via horizontal mattress; group H + K (n = 12) via horizontal mattress with knots thrown and, with each suture tail, 3 proximal, running-locking, Krackow-type passes on the radial and ulnar FDP sides with the suture ends tied together. We excluded 2 specimens from the H + K group because of improper anchor placement. All other fingers in both groups were individually mounted in an MTS machine for FDP loading in the following sequence for 500 cycles each: (1) to 15 N to simulate passive motion forces; (2) to 19 N for short-arc active motion forces; and (3) to 28 N for full active motion forces. Specimens that had not failed during cyclic testing were then loaded to failure. We measured FDP-to-bone gapping via a digital transducer. We defined failure as >3-mm gapping. RESULTS: The H + K group had significantly less gapping during cyclic loading up to 19 N and significantly higher load to failure. The H + K group failed exclusively at the anchor-bone level; the H group failed mostly by suture-tendon pullout. CONCLUSIONS: The H + K group performed significantly better regarding cyclic and load-to-failure testing after FDP reattachment. CLINICAL RELEVANCE: The H + K technique combines the benefits of horizontal-mattress tendon-to-bone apposition and Krackow-tendon locking. It converts the point of failure to the bone level rather than the suture-tendon level.

A Multicenter Prospective Randomized Comparison of Conduits Versus Decellularized Nerve Allograft for Digital Nerve Repairs.

PURPOSE: While there are advantages and disadvantages to both processed nerve allografts (PNA) and conduits, a large, well-controlled prospective study is needed to compare the efficacy and to delineate how each of these repair tools can be best applied to digital nerve injuries. We hypothesized that PNA digital nerve repairs would achieve superior functional recovery for longer length gaps compared with conduit-based repairs. METHODS: Patients (aged 18-69 years) presenting with suspected acute or subacute (less than 24 weeks old) digital nerve injuries were recruited to prticipate at 20 medical centers across the United States. After stratification to short (5-14 mm) and long (15-25 mm) gap subgroups, the patients were randomized (1:1) to repair with either a commercially available PNA or collagen conduit. Baseline and outcomes assessments were obtained either before or immediately after surgery and planned at 3-, 6-, 9-, and 12-months after surgery. All assessors and patients were blinded to the treatment arm. RESULTS: In total, 220 patients were enrolled, and 183 patients completed an acceptable last evaluable visit (at least 6 months and not more than 15 months postrepair). At last follow-up, for the short gap repair groups, average static two-point discrimination was 7.3 ± 2.8 mm for PNA and 7.5 ± 3.1 mm for conduit repairs. For the long gap group, average static two-point discrimination was significantly lower at 6.1 ± 3.3 mm for PNA compared with 7.5 ± 2.4 mm for conduit repairs. Normal sensation (American Society for Surgery of the Hand scale) was achieved in 40% of PNA long gap repairs, which was significantly more than the 18% observed in long conduit patients. Long gap conduits had more clinical failures (lack of protective sensation) than short gap conduits. CONCLUSIONS: Although supporting similar levels of nerve regeneration for short gap length digital nerve repairs, PNA was clinically superior to conduits for long gap reconstructions. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic I.

Passive Manipulation for Proximal Interphalangeal Joint Extension Contractures.

PURPOSE: We investigated closed passive manipulation as an alternative to surgery for certain proximal interphalangeal (PIP) joint extension contractures. METHODS: We retrospectively reviewed all patients with PIP joint extension contractures treated with passive manipulation at our institution between 2015 and 2019. The included patients were a minimum of 12 weeks from their initial injury/surgery (median 179 days; interquartile range: 130-228 days), had plateaued with therapy, and underwent a 1-time passive manipulation. All included fingers had congruent PIP joints and no indwelling hardware that could have had direct adhesions. Most (80%) patients had a direct injury to the finger ray(s) that led to the contractures. Most (75%) patients had the manipulation performed under local anesthesia in the office. Available measures of passive range of motion (PROM) and active range of motion (AROM) immediately, within 6 weeks, between 6 and 12 weeks, and at >12 weeks after the manipulation were recorded. RESULTS: Twenty-eight patients and 46 digits met the criteria. The median PIP joint PROM improved from 50° to 90° immediately following the manipulation. The median PROM values within 6 weeks, between 6 and 12 weeks, and at >12 weeks following manipulation were 80°, 85°, and 85°, respectively. The median AROM immediately after the manipulation improved from 40° to 90°, and the median AROM values within 6 weeks, between 6 and 12 weeks, and at >12 weeks were 70°, 50°, and 60°, respectively. None of the patients experienced worsening of PIP joint range of motion. One patient who had 4 fingers manipulated had a 45° distal interphalangeal joint extension lag for one of the fingers after the manipulation. Eight fingers underwent later flexor tenolysis or reconstruction to improve AROM after the gains in PROM via manipulation were maintained. CONCLUSIONS: Passive manipulation is an alternative to surgical release for select PIP joint extension contractures. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

The statistical fragility of studies on rotator cuff repair with graft augmentation.

BACKGROUND: Clinical decision-making often relies on evidence-based medicine. Our purpose was to determine the fragility index (FI) and fragility quotient (FQ) for studies evaluating rotator cuff repair (RCR) with graft augmentation. A lost to follow-up (LTF) value greater than the FI indicates statistical instability for the reported outcomes and conclusions. METHODS: We performed a systematic review using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines by searching PubMed, the Cochrane library, and Embase in June 2022 to identify studies of RCR with graft augmentation. Comparative studies with at least 1 statistically analyzed dichotomous outcome were included. Seventeen studies published in seven peer-reviewed journals from 2003 to 2019 were subsequently evaluated. The FI was determined by changing each reported outcome event within 2 × 2 contingency tables until statistical significance or nonsignificance was reversed. The associated FQ was determined by dividing the FI by the sample size. LTF values were also extracted from each included study. RESULTS: The included studies had a total of 1098 patients with 36 dichotomous outcomes. The associated median FI was 4 (interquartile range 2-5), indicating that the reversal of 4 patients' outcomes would have reversed the finding of significant difference. The median FQ was 0.08 (interquartile range 0.04-0.15), indicating that in a sample of 100 patients, reversal of 8 patients' outcomes would reverse statistical significance. The median number of patients LTF was 3 (range 0-25), with 56% of reported outcomes having LTF greater than their respective FI. CONCLUSION: Studies of RCR with graft augmentation lack statistical stability, with few altered outcome events required to reverse statistical significance. Larger comparative studies with better follow-up will strengthen the statistical stability of the evidence for RCR with graft augmentation. For future investigations and reports, we recommend including FI and FQ along with traditional statistical significance analyses to provide better context on the strength of conclusions.

Comparison of Lag Versus Nonlag Screw Fixation for Long Oblique Proximal Phalanx Fractures: A Biomechanical Study.

PURPOSE: To compare lag versus nonlag screw fixation for long oblique proximal phalanx (P1) fractures in a cadaveric model of finger motion via the flexor and extensor tendons. METHODS: We simulated long oblique P1 fractures with a 45° oblique cut in the index, middle, and ring fingers of 4 matched pairs of cadaveric hands for a total of 24 simulated fractures. Fractures were stabilized using 1 of 3 techniques: two 1.5-mm fully threaded bicortical screws using a lag technique, two 1.5-mm fully threaded bicortical nonlag screws, or 2 crossed 1.14-mm K-wires as a separate control. The fixation method was randomized for each of the 3 fractures per matched-pair hand, with each fixation being used in each hand and 8 total P1 fractures per fixation group. Hands were mounted to a custom frame where a computer-controlled, motor-driven, linear actuator powered movement of the flexor and extensor tendons. All fingers underwent 2,000 full flexion and extension cycles. Maximum interfragmentary displacement was continuously measured using a differential variable reluctance transducer. Our primary outcome was the difference in the mean P1 fragment displacement between lag and nonlag screw fixation at 2,000 cycles. RESULTS: The observed differences in mean displacement between lag and nonlag screw fixation were not statistically significant throughout all time points. A two one-sided test procedure for paired samples confirmed statistical equivalence in the fragment displacement between these fixation methods at all time points, including the primary end point of 2,000 cycles. CONCLUSIONS: Nonlag screws provided equivalent biomechanical stability to lag screws for simulated long oblique P1 fractures during cyclic testing in this cadaveric model. CLINICAL RELEVANCE: Fixation of long oblique P1 fractures with nonlag screws has the potential to simplify treatment without sacrificing fracture stability during immediate postoperative range of motion.

Surprise Out-of-Network Bills for Hand and Upper Extremity Trauma Patients.

PURPOSE: Patients may receive surprise out-of-network bills even when they present to in-network facilities. Surprise bills are common following emergency care. We sought to characterize and determine risk factors for surprise billing in hand and upper extremity trauma patients in the emergency department (ED). METHODS: We used IBM MarketScan data to evaluate hand and upper extremity trauma patients who received care in the ED from 2010 to 2017. Our primary outcome was the surprise billing incidence, defined as encounters in in-network EDs with out-of-network claims. We used descriptive and bivariate analyses to characterize surprise billing and used multivariable logistic regression to evaluate independent factors associated with surprise billing. RESULTS: Of 710,974 ED encounters, 97,667 (14%) involved surprise billing. The incidence decreased from 26% in 2010 to 11% in 2017. Mean coinsurance payments were higher for surprise billing encounters and had double the growth from 2010 to 2017 compared to those without surprise billing. Receiving care from different provider types-especially therapists, radiologists, and pathologists, as well as hand surgeons-was associated with significantly higher odds of surprise billing. Transfer to another facility was not significantly associated with surprise billing. CONCLUSIONS: Although the incidence of surprise billing decreased, more than 10% of patients treated in an ED for hand trauma remain at risk. Coinsurance for surprise billing encounters increased by twice as much as encounters without surprise billing. Patients requiring services from therapists, radiologists, pathologists, and hand surgeons were at greater risk for surprise bills. The federal No Surprises Act, passed in 2020, targets surprise billing and may help address some of these issues. CLINICAL RELEVANCE: Many hand and upper extremity patients requiring ED care receive surprise bills from various sources that result in higher out-of-pocket costs.

Applying Evidence to Inform Carpal Tunnel Syndrome Care.

Carpal tunnel syndrome (CTS) is one of the most common problems treated by hand surgeons. As our understanding of the condition has improved and focus on quality and evidence-based care has evolved, management of CTS has shifted as well. Although for many patients the diagnosis and treatment plan are relatively straightforward, understanding how to decide what diagnostics are appropriate, how to avoid complications especially in high-risk patients, and even which surgical option to offer remains a challenge. As CTS research efforts broaden and available evidence grows, understanding the different research findings in order to implement the evidence into practice is critical for all surgeons. In this article, we approach commonly encountered challenges in CTS management and take a methodological viewpoint to guide evidence-based practice.

Minimally Invasive Intramedullary Screw Versus Plate Fixation for Proximal Phalanx Fractures: A Biomechanical Study.

PURPOSE: To compare the maximum interfragmentary displacement of short oblique proximal phalanx (P1) fractures fixed with an intramedullary headless compression screw (IMHCS) versus a plate-and-screws construct in a cadaveric model that generates finger motion via the flexor and extensor tendons of the fingers. METHODS: We created a 30° oblique cut in 24 P1s of the index, middle, ring, and little fingers for 3 matched pairs of cadaveric hands. Twelve fractures were stabilized with an IMHCS using an antegrade, dorsal articular margin technique at the P1 base. The 12 matched-pair P1 fractures were stabilized with a radially placed 2.0-mm plate with 2 bicortical nonlocking screws on each side of the fracture. Hands were mounted to a frame allowing a computer-controlled, motor-driven, linear actuator powered movement of fingers via the flexor and extensor tendons. All fingers underwent 2,000 full-flexion and extension cycles. Maximum interfragmentary displacement was continuously measured using a differential variable reluctance transducer. RESULTS: The observed mean displacement differences between IMHCS and plate-and-screws fixation was not statistically significant throughout all time points during the 2,000 cycles. A 2 one-sided test procedure for paired samples confirmed statistical equivalence in fracture displacement between fixation methods at the final 2,000-cycle time point. CONCLUSIONS: The IMHCS provided biomechanical stability equivalent to plate-and-screws for short oblique P1 fractures at the 2,000-cycle mark in this cadaveric model. CLINICAL RELEVANCE: Short oblique P1 fracture fixation with an IMHCS may provide adequate stability to withstand immediate postoperative active range of motion therapy.

Assessing the Relationship Between Bone Density and Loss of Reduction in Nonsurgical Distal Radius Fracture Treatment.

PURPOSE: Whether low bone mineral density affects loss of reduction for distal radius fractures (DRFs) managed without surgery is unknown. Our purpose was to understand how bone mineral density, based on second metacarpal cortical percentage (2MCP) measurement, affects DRF healing after nonsurgical treatment. METHODS: We retrospectively reviewed 304 patients from 2 health systems with DRFs treated without surgery. The AO classification, 2MCP (<50% indicating osteoporosis), and fracture stability based on Lafontaine criteria were determined from prereduction radiographs. Radial inclination, radial height, volar tilt, ulnar variance, and intra-articular stepoff were measured on initial and 6-week final follow-up radiographs and compared. Bivariate analysis was used to evaluate the association between Lafontaine criteria or 2MCP and changes in radiographic parameters. Radiographic parameters with significant associations in bivariate analysis were evaluated in multivariable models adjusted for age, sex, initial radiographic parameters, reduction status, and AO fracture type. RESULTS: Across all patients, after 6 weeks of nonsurgical treatment, ulnar variance (shortening of the radius) increased by an average of 1.4 mm. Bivariate analysis showed that lower 2MCP and unstable fractures per Lafontaine criteria were each significantly associated with an increase in ulnar variance (P < .05). In adjusted multivariable models, having both 2MCP less than 50% and an unstable fracture together was associated with an additional 1.2-mm increase in ulnar variance (P < .05). CONCLUSIONS: A 2MCP in the osteoporosis range and unstable fractures by Lafontaine criteria were each associated with a significant increase in ulnar variance after nonsurgical treatment for DRFs. Patients with unstable fractures and 2MCP less than 50% are likely to have an additional increase of greater than 1 mm in ulnar variance at the end of nonsurgical fracture treatment than patients with similar injuries, but without these features. Using initial radiographs to identify patients with low bone mineral density that may be at risk for more substantial loss of reduction can assist with decision making for managing DRFs. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

Biomechanical Analysis of Zone 2 Flexor Tendon Repair With a Coupler Device Versus Locking Cruciate Core Suture.

PURPOSE: To compare flexor tendon repair strength and speed between a tendon coupler and a standard-core suture in a cadaver model. METHODS: In 5 matched-pair fresh cadaver hands, we cut the flexor digitorum profundus tendon of each finger in zone 2 and assigned 20 tendons to both the coupler and the suture groups. Coupler repair was with low-profile stainless steel staple plates in each tendon stump, bridged by polyethylene thread. Suture repair was performed using an 8-strand locking-cruciate technique with 4-0 looped, multifilament, polyamide suture. One surgeon with the Subspecialty Certificate in Surgery of the Hand performed all repairs. Via a load generator, each flexor digitorum profundus was loaded at 5 to 10 N and cycled through flexion just short of tip-to-palm and full extension at 0.2 Hz for 2,000 cycles to simulate 6 weeks of rehabilitation. We recorded repair gapping at predetermined cycle intervals. Our primary outcome was repair gapping at 2,000 cycles. Tendons that had not catastrophically failed by 2,000 cycles were loaded to failure on a servohydraulic frame at 1 mm/s. RESULTS: Tendon repair gapping was similar between coupled and sutured tendons at 2,000 cycles. Tendons repaired with the coupler had higher residual load to failure than sutured tendons. Mean coupler repair time was 4 times faster than suture repair. CONCLUSIONS: Zone 2 flexor repair with a coupler withstood simulated early active motion in fresh cadavers. Residual load to failure and repair speed were better with the coupler. CLINICAL RELEVANCE: This tendon coupler may eventually be an option for strong, reproducible, rapid flexor tendon repair.

The Relationship Between Hemihamate Graft Size and Proximal Interphalangeal Joint Flexion for Reconstruction of Fracture-Dislocations: A Biomechanical Study.

PURPOSE: The purpose of this study was to determine the relationship between hemihamate graft size and proximal interphalangeal (PIP) joint flexion in a biomechanical fracture-dislocation model. METHODS: We simulated middle finger PIP fracture-dislocations in 5 cadaver hands by resecting 50% of the palmar articular surface of the middle phalanx (P2) base. Fluoroscopy was used to confirm dorsal subluxation of the middle phalanx base after resection. A 10-mm osteochondral hamate graft was contoured to reconstruct the volar lip of the middle phalanx and was progressively downsized by 2-mm increments for each trial. A computer-controlled articulator and jig simulated active flexion and extension of the fingers. Maximum PIP flexion was measured at each graft size using fluoroscopy and digital imaging software. Clinically significant flexion block was defined as PIP flexion less than 90°. RESULTS: The actual mean size of the volar defect created was 52% (3.5 mm) of the middle phalanx articular surface, which created instability and dorsal subluxation in all tested fingers. After hemihamate reconstruction, all specimens were stable throughout flexion and extension for all graft sizes. A flexion block of 90° occurred at a mean graft size of 191% of the defect (6.5 mm). With regard to the volar lip of the P2, grafts that projected an average 0.8 mm past the native volar lip position had 98° (range, 84°-107°) maximum PIP flexion. Grafts that projected an average of 3.1 mm past the native volar lip position had 90° (range, 69°-100°) maximum PIP flexion. Linear regression modeling incorporating all of the results predicted flexion block to occur at a graft size as small as 166% of the 50% volar P2 defect. In this model, for every 50% (1.7-mm) increase in graft size relative to the defect, PIP flexion decreased by approximately 6°. CONCLUSIONS: Nonanatomical hemihamate grafts produce a PIP flexion block at extreme sizes, predicted to occur at greater than 166% of a 50% P2 base articular defect in our model. This suggests that relatively large grafts can be used for reconstruction of PIP fracture-dislocations without substantial biomechanical block to PIP flexion. We suggest sizing no larger than 3 mm past the native P2 volar lip position to avoid an important mechanical block to PIP flexion. CLINICAL RELEVANCE: The information from this study helps surgeons understand how large a hemihamate graft can be used for P2 volar base reconstruction before having a negative impact on PIP flexion.

The Effect of Skin Pigmentation on Determination of Limb Ischemia.

PURPOSE: Timely identification of tissue ischemia is critical, both in the traumatized limb and following free tissue transfer. The purpose of this study was to determine if skin pigmentation affects the ability to detect limb ischemia. METHODS: We conducted a study of healthy controls exposed to limb ischemia. The subjects were classified based on skin pigmentation using a defined skin type assessment tool, a visual color scale, and self-description of race. Participants were randomized by limb and tourniquet status; surgeons were blinded to both. Ischemia was induced by tourniquet insufflations, and board-certified orthopedic and plastic surgeons who had completed an accredited hand surgery fellowship conducted physical examinations. The surgeons monitored the forearms at 2, 6, and 10 minutes based on appearance of ischemia, capillary refill, and color in 3 locations on the limbs (posterior interosseous artery flap skin territory, radial forearm flap skin territory, and the digits). RESULTS: We found a significant decrease in the ability to detect ischemia in participants with increased skin pigmentation, as documented by all metrics, when evaluating the posterior interosseous artery and radial forearm flap skin territories at all time points. For example, when monitoring the posterior interosseous artery flap with the tourniquet insufflated at time 10 minutes, 92.9% of Caucasians were correctly identified as being ischemic whereas only 23.3% of African Americans were correctly identified. CONCLUSIONS: Skin pigmentation significantly affects the identification of an ischemic limb/skin flaps on physical examination. Whereas the standard treatment for monitoring of free tissue transfer is clinical examination, that may not be sufficient for patients with increased skin pigmentation. Surgeons should exercise particular vigilance during physical examination of a potentially ischemic limb/skin flaps with greater skin pigmentation. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II.

Scapholunate kinematics of asymptomatic wrists in comparison with symptomatic contralateral wrists using four-dimensional CT examinations: initial clinical experience.

OBJECTIVES: Using four-dimensional CT scan (4DCT), we aimed at showing the kinematics of scapholunate (SL) interval in asymptomatic wrists in comparison with symptomatic contralateral wrists with inconclusive radiographic findings. METHODS: This is an IRB approved, HIPPA compliant, retrospective study. Patients suspected of SL interosseous ligament (SLIL) injuries were referred for further evaluation of chronic wrist pain (>3 months). Twelve wrists (11 subjects) with chronic symptoms and inconclusive plain radiographs and 10 asymptomatic wrists (in 10 different subjects) were scanned using 4DCT. The minimum SL interval was measured during three wrist motions: relaxed-to-clenched fist, flexion-to-extension, and radial-to-ulnar-deviation. Changes were recorded using double-oblique multiplanar reformation technique. RESULTS: We extracted the normal limits of the SL interval as measured by dynamic CT scanning during active motion in asymptomatic wrists. In asymptomatic wrists, the average SL interval was observed to be smaller than 1 mm during all motions. In symptomatic wrists, during exams performed with clenched fist (SL interval (mean ± SD) = 2.53 ± 1.19 mm), extension (2.54 ± 1.48 mm) or ulnar deviation (2.06 ± 1.12 mm), the average SL interval was more than 2 mm. In contrast to symptomatic wrists, no significant change in SL interval measurements was detected during wrist motions in asymptomatic wrists. There was a mild to moderate correlation between SL interval change and presence/absence of symptoms (point-biserial correlation coefficients: 0.29-0.55). CONCLUSION: In patients with wrist pain suspicious for SLIL injury and inconclusive radiographs, SL interval increase can be detected with 4DCT in the symptomatic wrist compared to the asymptomatic wrist.

Hook Plate Versus Suture Anchor Fixation for Thumb Ulnar Collateral Ligament Fracture-Avulsions: A Cadaver Study.

PURPOSE: To compare the biomechanical properties of hook plate fixation and suture anchor fixation for collateral ligament fracture-avulsions of the thumb metacarpophalangeal ulnar collateral ligament (UCL). METHODS: A thumb UCL fracture-avulsion model was created in 7 matched pairs of cadaver hands. An osteotomy was made parallel to the shaft of the proximal phalanx along the entire insertion of the UCL. The simulated fracture was secured using either a suture anchor tied over bone tunnels in the avulsion fragment or with a hook plate. Specimens were mounted on a servohydraulic load frame and loaded to failure. Motion perpendicular to the osteotomy was measured using an implanted 3-mm differential variable reluctance transducer device. Differences in load to failure and construct stiffness were compared and analyzed using a t test. RESULTS: The hook plate construct failed at significantly higher loads than suture fixation. Mean load to failure in the hook plate construct was 58 N (± 20 N) compared with 27 N (± 19 N) in the suture anchor construct. The difference in construct stiffness was 49 N/mm (± 17 N/mm) for the plate compared with 7 N/mm (± 13 N/mm) for the suture anchor. The main mechanism of failure for the hook plate construct was screw pullout or screw bending. The usual mechanism of failure for the suture anchor construct was anchor pullout. CONCLUSIONS: The hook plate construct was biomechanically superior to the suture anchor construct for fixation of thumb metacarpophalangeal joint UCL fracture-avulsions with regard to load to failure. CLINICAL RELEVANCE: The hook plate construct provides stronger fixation than a suture anchor for thumb UCL fracture-avulsions.

Changes in Wrist Motion After Simulated Scapholunate Arthrodesis: A Cadaveric Study.

PURPOSE: A high incidence of nonunion and relatively poor outcomes with prior fixation techniques has precluded scapholunate (SL) arthrodesis as a standard treatment for SL instability. Our purpose was to determine the impact on range of motion (ROM) of simulated SL arthrodesis via headless screw fixation. METHODS: We performed baseline wrist ROM for 10 cadaveric wrists using a standardized mounting-and-weights system. Extension, flexion, radial deviation, ulnar deviation, dart-thrower's extension, and dart-thrower's flexion were assessed. Two 3.0-mm headless compression screws were inserted across the SL joint to simulate SL arthrodesis. Goniometric measurements and fluoroscopic imaging were repeated to assess ROM differences after simulated SL arthrodesis. We assessed SL angle and gap during testing to ensure there was no significant motion between the scaphoid and lunate, thus confirming stable simulated fusion. Differences in ROM were compared between baseline and simulated SL arthrodesis using paired t tests. RESULTS: Mean SL angle remained constant between pre- and post-arthrodesis imaging (47° ± 6° vs 46° ± 4°) and did not change during post-arthrodesis ROM testing, indicating a stable simulated fusion. Compared with baseline, SL arthrodesis had a statistically significant reduction in maximum flexion of 6° and 9° based on fluoroscopy and goniometry, respectively, in dart-thrower's extension of 5° and 9° based on fluoroscopy and goniometry, respectively, and in dart-thrower's flexion of 6° for both fluoroscopy and goniometry. No other ROMs after simulated SL arthrodesis were significantly different compared with baseline. CONCLUSIONS: The effects of simulated SL arthrodesis on radiocarpal and midcarpal motion compare favorably with motion after SL soft tissue repair and other reconstructive techniques that have been previously reported. The statistically significant decreases in wrist flexion and dart-thrower's extension-flexion after simulated SL arthrodesis are of questionable clinical importance. CLINICAL RELEVANCE: These results may support reconsidering SL arthrodesis as a viable treatment option for acute or chronic SL instability with regard to apparent minimal adverse effects on functional wrist ROM.

Biomechanical characteristics of hemi-hamate reconstruction versus volar plate arthroplasty in the treatment of dorsal fracture dislocations of the proximal interphalangeal joint.

PURPOSE: To compare stability and range of motion after hemi-hamate reconstruction versus volar plate arthroplasty in a biomechanical proximal interphalangeal (PIP) joint fracture-dislocation model. METHODS: Eighteen digits from 6 cadaver hands were tested. We created defects of 40%, 60%, and 80% in the palmar base of each digit's middle phalanx, simulating an acute PIP joint fracture-dislocation. Each defect scenario was reconstructed with a hemi-hamate arthroplasty followed by a volar plate arthroplasty. A computer-controlled mechanism was used to bring each digit's PIP joint from full extension to full flexion via the digital tendons in each testing state, and in the intact state. During each testing scenario we collected PIP joint cinedata in a true lateral projection using mini-fluoroscopy. A digital radiography program was used to measure the amount of middle phalanx dorsal translation (subluxation) in full PIP joint extension. We recorded the angle at which subluxation, if present, occurred during each testing scenario. RESULTS: Average dorsal displacement of the middle phalanx in relation to the proximal phalanx was 0.01 mm for the hemi-hamate reconstructed joints and -0.03 mm for the volar plate arthroplasty, compared with the intact state. Flexion contractures were noted in each of the specimens reconstructed with volar plate arthroplasty. Degree of contracture was directly correlated with defect size, averaging 20° for 40% defects, 35° for 60% defects, and 60° for 80% defects. We observed no flexion contractures in the hemi-hamate reconstructions. CONCLUSIONS: Surgeons can use both hemi-hamate and volar plate arthroplasty to restore PIP joint stability following a fracture dislocation with a large middle phalanx palmar base defect. Use of volar plate arthroplasty led to an increasing flexion contracture as the middle phalanx palmar base defect increased. CLINICAL RELEVANCE: Clinicians can use the information from this study to help with surgical decision-making and patient education.

Two versus 3 lag screws for fixation of long oblique proximal phalanx fractures of the fingers: a cadaver study.

PURPOSE: To compare 2- versus 3-screw fixation for oblique fractures of the proximal phalanx in a cadaver model that simulates active finger motion. METHODS: We experimentally cut the proximal phalanges of the index, middle, and ring fingers of 9 cadaveric hands. Five fingers were assigned to a control group with no fixation, and 22 were fixed with either 2 or 3 lag screws. One digit was excluded because of iatrogenic fracture during preparation. The fingers were fitted with a differential variable reluctance transducer that measured maximum interfragment displacement while the fingers were subjected to 2,000 full flexion and extension cycles to simulate a 6-week active motion protocol. RESULTS: Analysis of variance revealed a significant difference between the control group and both the 2- and the 3-screw group. The 2- and 3-screw group average displacements were not significantly different. Both of these groups were equivalent with a power of 90%. CONCLUSIONS: Biomechanical stability during simulated active motion protocol did not differ in simulated proximal phalanx fractures treated with 2 lag screws or 3. CLINICAL RELEVANCE: Fracture fixation using 2 screws may be more cost and time effective and, therefore, more attractive to the surgeon, even when 3 screws can be placed. Furthermore, surgeons may consider using 2 screws rather than resorting to plate fixation when 3-screw fixation is not possible for these types of fractures.

Dynamic evaluation of pisotriquetral instability using 4-dimensional computed tomography.

The authors described 2 cases of pisotriquetral instability, which were diagnosed in patients presenting with ulnar wrist clicking and pain. The diagnosis was made first using 4-dimensional computed tomography, which helped further interventions and management in both patients.