Comparison of the "contact biomechanics" of the intact and proximal row carpectomy wrist

Scapholunate Advanced Collapse (SLAC) and Scaphoid Nonunion Advanced Collapse (SNAC): A Review of Treatment Options for Stage II

Scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) represent clinical entities identified by a pattern of predictable degenerative changes. They are the most common causes of wrist arthritis. Both entities can remain asymptomatic for many years and may go undiagnosed. Diagnosis is usually confirmed through clinical examination, which reveals progressive wrist pain and instability. Radiographically, degenerative changes in the radiocarpal and midcarpal joints are present, as well as nonunion of the scaphoid fracture in SNAC. The management differs according to the stage. Particularly in this review article, we reviewed the treatment options for stage II SLAC and SNAC wrist. In addition to the well-described surgical techniques such as proximal row carpectomy and four-corner fusion, alternatives such as capitolunate arthrodesis, three-corner fusion, and soft tissue procedures like capsulodesis and tenodesis are available. Proximal row carpectomy and partial arthrodeses yield comparable results. Soft tissue procedures are viable alternatives and are preferred in younger patients to avoid early salvage operations.

Proximal Row Carpectomy Does Not Alter Contact Pressures of the Lunate Fossa: A Cadaveric Study

BACKGROUND

Previous studies have suggested that proximal row carpectomy (PRC) results in increased contact pressures and decreased contact areas in the radiocarpal joint. Such experiments, however, used older technologies that may be associated with considerable measurement errors. The purpose of this study was to determine whether there was a significant difference in contact pressure and contact area before and after PRC using Tekscan, a newer pressure sensing technology.

METHODS

Ten nonpaired cadaveric specimens were dissected proximal to the carpal row and potted. An ultra-thin Tekscan sensor was secured in the lunate fossa of the radius. The wrists were loaded with 200 N of force for 60 seconds to simulate clenched-fist grip; contact pressure and area was assessed before and after PRC.

RESULTS

Performing a PRC did not significantly increase mean contact pressure at the lunate fossa compared to the native state (mean increase of 17.4 ± 43.2 N/cm2, P = .184). Similarly, the PRC did not significantly alter peak contact pressures at the lunate fossa (intact: 617.2 ± 233.46 N/cm2, median = 637.5 N/cm2; PRC: 707.8 ± 156.6 N/cm2, median = 728.5 N/cm2; P = .169). In addition, the PRC (0.46 ± 0.15 cm2, median = 0.48 cm2) and intact states (0.49 ± 0.25 cm2, median = 0.44 cm2) demonstrated similar contact areas (P = .681).

CONCLUSIONS

In contrast to prior studies that demonstrated significant increases in contact pressure and decreases in contact area after PRC, our findings propose that performing a PRC does not significantly alter the contact pressures or area of the lunate fossa of the radiocarpal joint.

Biomechanics of Proximal Hamate Autograft in Scaphoid Nonunion

Purpose  Treatment of proximal scaphoid fractures remains a challenge with a risk of nonunions and avascular necrosis due to its retrograde blood supply. The ipsilateral proximal hamate has been described as a viable autograft option for osteochondral reconstruction of the proximal scaphoid. Our study evaluated the changes in the contact area and pressure of the radioscaphoid joint after proximal hamate autograft reconstruction. Methods  Thin sensors (Tekscan Inc., Boston, MA) were placed in the radiocarpal joints of six fresh-frozen cadaveric forearms. Each specimen's tendons were loaded to 150 N in neutral, 45-degree flexion/extension positions through five cycles. Through a dorsal wrist approach, the proximal 10 mm of the scaphoid and hamate was excised. The proximal hamate autograft was affixed to the scaphoid with K-wires. Peak contact pressures and areas at the scaphoid facet were determined and averaged across loading cycles. Results  At the radioscaphoid facet, peak contact pressures were equivalent, although an increasing trend in the neutral and extended wrist position was seen. At the radiolunate facet, contact pressure had an increasing trend in the hamate reconstructed wrists in all wrist positions. Contact areas had a decreasing trend and were nonequivalent at the radioscaphoid facet in the hamate reconstructed wrist. Conclusion  After hamate autograft, the contact areas were not equivalent between the native and reconstructed wrists but contact pressures were equivalent in the facets. The proximal hamate has a more pointed morphology compared with the proximal scaphoid, which would explain the change in contact area in the hamate autografted wrist. Our study suggests hamate autograft may present a viable reconstruction for the proximal pole of the scaphoid without significantly altering peak contact pressures at the radioscaphoid facet.

A Volar Locking Plate With Fossa Specific Fixation Provides Comparable Stability Between Articular and Nonarticular Cadaveric Models of Distal Radius Fracture

BACKGROUND

Distal radius fractures often present with a 3-part articular fragmentation pattern, with separation of the dorsal and volar lunate fossa. The column concept of distal radius fixation addresses the importance of stabilizing both the scaphoid fossa lateral column and the lunate fossa intermediate column. Recent evidence strengthens the value of immediate postoperative mobilization. Satisfactory outcomes following these protocols are predicated on volar locking plates (VLPs) providing adequate stability to the fracture repair. We hypothesize that a VLP which individually supports both lateral and intermediate distal radius columns may provide comparable stability between articular and non-articular cadaveric fracture models under parameters meant to simulate postoperative loading.

METHODS

Eleven cadaveric matched pair specimens were randomized to receive a simulated AO Type A2 non-articular distal radius fracture on one side with an AO Type C3 articular fracture on the contralateral side. Stiffness during cyclic loading was compared between fracture groups. A matched-paired Student t-test was used to determine statistical significance (P = .05).

RESULTS

There were no significant differences (P = .35) in stiffness between the articular models (mean 370.0 N/mm, +/-93.5) and the non-articular models (360.4 N/mm, +/-60.0) of distal radius fracture.

CONCLUSION

A VLP that individually supports the scaphoid and lunate fossa with fixed angle subchondral support may provide comparable fixation strength with resistance to displacement between articular and non-articular fracture patterns. The current results suggest that fossa-specific VLP fixation in articular fractures can maintain construct stability during postoperative loading.

Assessment and Management of Acute Volar Rim Fractures

The volar rim of the distal radius is the only bony restraint to volar carpal subluxation. Higher loads across the volar rim require stable and rigid fixation to maintain reduction and allow healing while rehabilitation begins. Volar marginal fragments are not amenable to buttressing by fixed angle volar locking plates. Appropriate management of volar marginal fragments comprises two steps-recognition of their presence and rigid anatomical repair. The best opportunity for success in the presence of a volar marginal fragment is its adequate initial treatment. The purpose of this review is to reinforce the importance of a complete preoperative and intraoperative evaluation of distal radius fractures. Volar marginal fragments can easily be overlooked even following initial reduction and fixation. Understanding the relevant anatomy and loading parameters can facilitate intraoperative decisions on approach and fixation, which are integral to achieving optimal clinical outcomes.

Anatomy, Biomechanics, and Loads of the Wrist Joint

The wrist is by far the most differentiated section of the musculoskeletal system. The spectrum of wrist injuries ranges from minor injuries to complex traumas with simultaneous loss of functions, resulting in enormous economic costs. A proper understanding of the anatomy and biomechanics is essential for effective treatment, whether conservative or surgical; this applies to the wrist no less than to other parts of the human body. Here; information on the wrist anatomy; kinematics; and biomechanical behavior is presented, commencing with a brief explanation of the structure of its hard and soft tissues. Eight carpal bones in combination with two forearm bones (radius and ulna) construct the wrist joint. The motion of the wrist joint is initiated by the muscles of the forearm, and strong and short ligaments ensure the stability of the wrist. All of these components are essential to bringing functions to the wrist joint because these structures allow wrist mobility and sustainability. In addition, the kinematics of the wrist joint is presented and different biomechanical model approaches. The therapeutic (surgical) restoration of the balance between the load–bearing capacity and the actual stress on a joint is the prerequisite for a lifelong and trouble-free function of a joint. Regarding the complex clinical problems, however, a valid biomechanical wrist joint model would be necessary as assistance, to improve the success of systematized therapies based on computer–aided model–based planning and intervention.

In vivo articular contact pattern of a total wrist arthroplasty design

Total wrist arthroplasty (TWA) designs suffer from relatively high complication rates when compared to other arthroplasties. Understanding the contact pattern of hip and knee replacement has improved their design and function; however, the in vivo contact pattern of TWA has not yet been examined and is thus the aim of this study. We hypothesized that the center of contact (CoC) is located at the geometric centers of the carpal component and radial component in the neutral posture and that the CoC moves along the principal arcs of curvature throughout primary anatomical motions. Wrist motion and implant kinematics of six patients with the Freedom® total wrist implant were studied during various tasks using biplanar videoradiography. The location of the CoC of the components was investigated by calculating distance fields between the articular surfaces. We found the CoC at the neutral posture was not at the geometric centers but was located 3.5 mm radially on the carpal component and 1.2 mm ulnarly on the radial component. From extension to flexion, the CoC moved 10.8 mm from dorsal to volar side on the carpal component (p < 0.0001) and 7.2 mm from volar to dorsal on the radial component (p = 0.0009). From radial to ulnar deviation, the CoC moved 12.4 mm from radial to ulnar on the carpal component (p < 0.0001), and 5.6 mm from ulnar to radial on the radial component (p = 0.009). The findings of this study may eventually improve TWA success by advancing future designs through a more accurate understating of their kinematic performance in vivo.

The Effect of Forearm Position on Wrist Joint Biomechanics

PURPOSE

All active motion wrist joint simulators have been designed to simulate physiologic wrist motion; however, a main difference among them is the orientation of the forearm (horizontal or vertical with respect to gravity). Moreover, the effect of forearm orientation on experimental results has yet to be quantified, but it may be an important variable. Thus, the purpose of this study was to determine the effect of forearm orientation on wrist kinematics and contact mechanics.

METHODS

Eight cadaveric upper limbs were cycled through a flexion-extension motion using an active motion wrist simulator. Motion trials were performed in 3 forearm orientations (gravity-neutral, gravity-flexion, and gravity-extension). A computed tomography-based joint congruency technique was used to examine radiocarpal joint contact and joint contact centroid translation in the 3 tested orientations.

RESULTS

At full wrist extension and wrist flexion, radioscaphoid contact area was greatest in the gravity-extension orientation. Radiolunate contact area was similar among all 3 forearm orientations. The radioscaphoid contact centroid was consistent among the 3 tested positions with the wrist in neutral wrist position. In contrast, the radioscaphoid contact centroid translated radially in the gravity-neutral position relative to the gravity-flexion position in extreme extension. There were no differences in radiolunate centroid contact position in the 3 forearm orientations.

CONCLUSIONS

This study demonstrates that forearm orientation affects contact mechanics and end-range carpal kinematics. Future biomechanical studies should report forearm orientation and discuss the implication of the forearm orientation used on the experimental results.

CLINICAL RELEVANCE

This study provides evidence that the wrist joint is sensitive to forearm positions consistent with activities of daily living and rehabilitation protocols.

Progressing arthrosis and a high conversion rate 11 (4-19) years after four corner fusion

Four corner fusion (4CF) is a limited wrist arthrodesis offered to patients with painful wrists due to scaphoid non-union advanced collapse (SNAC) or scapho-lunate advanced collapse (SLAC). A retrospective study of 42 wrists (in 36 patients), operated with 4CF using K-wires and autologous bone graft followed up after 11 (4-19) years was performed, 25 were male and mean age at surgery was 51 (22-71) years. During the follow-up period, 13 wrists were converted to total wrist arthrodesis or wrist arthroplasty, and one is scheduled for conversion (14/42, 33%) due to non-union (3), DISI and progressing arthrosis (7) or progressing arthrosis (4). Non-union was seen in 3/42 (93%) wrists, all were later converted. At the final follow-up, the patients reported residual pain, VAS = 15 and 36 at rest and activity, respectively, and QDASH/PRWHE = 32 and 31, respectively. Active range of motion (AROM) was 38% and grip-strength was 76% compared to the uninjured side. Degenerative changes were seen in 88% on CT scans at follow-up. 4CF renders an acceptable pain reduction and function in the majority of patients, but increased degeneration and a high number of conversions after a longer follow-up time is concerning.

Management of scapholunate advanced collapse and scaphoid nonunion advanced collapse without proximal row carpectomy or four corner fusion

Four corner arthrodesis and proximal row carpectomy are the most common techniques for the management of advanced radiocarpal arthritis due to longstanding scapholunate instability and scaphoid nonunion. The advantages and short comings of each technique have been well defined in the literature. Advancements in joint replacement and arthroscopic surgery have resulted in new operations to manage radiocarpal and midcarpal arthritis. Most of these new procedures are modifications of the two classical operations, but some use modern implants and newer materials. New individualized options, like osteochondral grafting in combination with proximal row carpectomy or (arthroscopic) distal resection of the scaphoid, allowed us to improve our treatment and offer patients less invasive but equally effective procedures. We consider that four corner arthrodesis and proximal row carpectomy should not always be standard management for advanced radiocarpal arthritis.

Vascularized Capitate Transposition for the Treatment of Stage IIIB Kienböck Disease

PURPOSE

The treatment of Kienböck disease (KD) continues to be controversial. In this study, we report the long-term follow-up outcomes of patients who were diagnosed with stage IIIB KD treated with vascularized capitate transposition.

METHODS

A total of 16 patients were retrospectively reviewed. Baseline clinical information was extracted from medical records, and wrist function was clinically evaluated, including x-ray images.

RESULTS

At the final follow-up, wrist pain was severe in 0 patients, moderate in 2 patients, mild in 5 patients, and absent in 9 patients. The mean postoperative active flexion and extension of the affected wrist was significantly improved after surgery compared with before surgery. The postoperative and preoperative mean grip strength was 35 kg and 27 kg, respectively. The Disabilities of the Arm, Shoulder, and Hand score was significantly improved after surgery compared with before surgery.

CONCLUSIONS

Vascularized capitate transposition for the treatment of Lichtman stage IIIB KD is feasible and associated with improvements in wrist function and pain.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

The Use of Contact Biomechanics to Study the Intact, Proximal Row Carpectomy and Scaphoid Excision, Four Bone Fusion Wrist

The study of contact biomechanics of the wrist is a challenge. This is partly due to the relatively small size of the joint as well as the lack of space in the radiocarpal joint which makes the delivery of investigative materials such as pressure sensitive film without causing artifact, difficult. Fortunately, a number of authors have studied the intact wrist, the scapholunate ligament injured wrist, the proximal row carpectomy and the scaphoid excision, four bone fusion. Despite some contrasting findings, there are some general concepts that we understand about wrist mechanics.

Functional Outcomes After Salvage Procedures for Wrist Trauma and Arthritis (Four-Corner Fusion, Proximal Row Carpectomy, Total Wrist Arthroplasty, Total Wrist Fusion, Wrist Denervation): A Review of Literature

Background:

Several salvage procedures for the arthritically destroyed wrist exist. Each of these has advantages as well as disadvantages.

Aims:

The aim of this article is to give practical insights for the clinician on: (1) biomechanical and clinical fundamentals of normal and impaired wrist motion; (2) difficulties in assessment of postoperative outcome between measured motion by the surgeon and self-reported outcome by the patient; (3) indications for each procedure; and (4) differences in functional outcome between partial and complete motion-preserving as well as complete motion-restricting salvage procedures.

Methods:

In trend, Proximal Row Carpectomy (PRC) is slightly superior over four-corner fusion (4CF) in terms of functional outcome, but the methodology-related postoperative motion is decreased for both procedures. Furthermore, PRC is easier to perform, needs lower costs, and has fewer complications than 4CF. Total Wrist Arthroplasty (TWA) has the advantage compared to PRC and 4CF that the preoperative motion values are preserved, but it is limited by decreased load-bearing capacity for the wrist. Total Wrist Fusion (TWF) is associated with a higher load-bearing capacity for the wrist than TWA, but it is limited for carrying out essential activities of daily living. Both PRC and 4CF can be combined primarily by wrist denervation. Wrist denervation alone does not impair the movement of the wrist.

Results and Conclusion:

Salvage procedures for the arthritically destroyed wrist should be detected regarding patients age- and gender-related claims in work and leisure. Not all of them can be successfully re-employed in their original occupations associated with high load-bearing conditions.

Mid-term outcomes of routine proximal row carpectomy compared with proximal row carpectomy with dorsal capsular interposition arthroplasty for the treatment of late-stage arthropathy of the wrist

AIMS

The aims of this study were to compare the mid-term outcomes of patients with late-stage arthritis of the wrist treated with proximal row carpectomy (PRC) and dorsal capsular interposition (DCI) arthroplasty with a matched cohort treated with routine PRC alone.

PATIENTS AND METHODS

A total of 25 arthritic wrists (24 patients) with pre-existing degenerative changes of the proximal capitate and/or the lunate fossa of the radius were treated with PRC + DCI over a ten-year period. This group of patients were matched 1:2 with a group of 50 wrists (48 patients) without degenerative changes in the capitate or lunate fossa that were treated with a routine PRC alone during the same period. The mean age of the patients at the time of surgery was 56.8 years (25 to 81), and the demographics and baseline range of movement of the wrist, grip strength, Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, and Patient-Rated Wrist Evaluation (PRWE) score were similar in both groups.

RESULTS

At a mean follow-up of 5.9 years (1.8 to 11.8), significant improvements in mean grip strength, the flexion-extension arc of movement of the wrist, QuickDASH, and PRWE scores were seen in both groups. There was no diifference between the groups for any of the outcomes. One patient in the PRC + DCI group required additional surgery for a deep infection, while two in the PRC group had complications (one wound dehiscence requiring revision closure, one transient radial sensory neuritis). One patient in each group required total arthrodesis of the wrist for progressive degenerative radiocarpal changes. A total of 70 patients (93%) were satisfied with the outcomes.

CONCLUSION

PRC with DCI is an effective form of treatment for late-stage arthritis of the wrist involving the capitolunate joint, with mid-term outcomes that are similar to those in patients without degenerative changes affecting the capitate or lunate fossa who are treated with a routine PRC alone. Cite this article: Bone Joint J 2018;100-B:197-204.

Four-Year Outcomes of Midcarpal Hemiarthroplasty for Wrist Arthritis

PURPOSE

The purpose of this study was to review the average 4-year outcomes of a cohort of patients with wrist arthritis, treated by a single surgeon with a novel prosthetic hemiarthroplasty of the midcarpal joint. We hypothesized that midcarpal hemiarthroplasty would improve range of motion and grip strength of patients with wrist arthritis, with a complication profile comparable with that of alternative solutions for wrist arthritis.

METHODS

We reviewed a series of 20 patients treated with a midcarpal hemiarthroplasty at an average of 4 years following surgery. Patients were evaluated objectively with grip strength, wrist range of motion, serial radiographs, and subjectively surveyed with Disabilities of the Arm, Shoulder, and Hand (DASH) and Mayo scores.

RESULTS

Range of motion increased by a mean 33° in flexion-extension and 10° in radial-ulnar deviation compared with preoperative range of motion. Mean grip strength improved to 20.8 kg from 14.1 kg, and Mayo and DASH scores also significantly improved. Three patients had a manipulation under anesthesia for stiffness. One patient required open reduction internal fixation of an unstable fourth carpometacarpal joint after falling. Two patients were revised to a total wrist arthroplasty and 1 to a wrist fusion.

CONCLUSIONS

Midcarpal hemiarthroplasty provides improved wrist range of motion, grip strength, and patient-reported outcome scores compared with preoperative values, with a complication profile comparable with that of other surgical options for patients with wrist arthritis. Advantages of midcarpal arthroplasty include retention of the native distal carpal row, preservation of midcarpal motion, as well as the option for conversion to a total wrist arthroplasty should revision be required.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Four-dimensional rotational radiographic scanning of the wrist in patients after proximal row carpectomy

We measured cartilage thickness, contact surface area, volume of the capitate and shape of the capitate during motion in the operated and unaffected wrists of 11 patients with a mean follow-up of 7.3 years after proximal row carpectomy. Radiocapitate cartilage thickness in the operated wrists did not differ significantly from radiolunate cartilage thickness in the unaffected wrists. The radiolunate surface area was significantly less than the radiocapitate surface area. The volume of the capitate was significantly increased in the operated wrists. The shape of the capitate changed significantly in two of three orthogonal directions. The combination of remodelling of the capitate, increase in its surface area and intact cartilage thickness could help to explain the clinical success of proximal row carpectomy.

Proximal Row Carpectomy and 4-Corner Arthrodesis in Patients Younger Than Age 45 Years

PURPOSE

To examine the long-term outcome of patients aged less than 45 years who underwent either proximal row carpectomy (PRC) or 4-corner arthrodesis (4CA) for wrist arthritis.

METHODS

We reviewed a retrospective cohort of 89 patients aged less than 45 years who underwent either 4CA (n = 51) or PRC (n = 38) for wrist arthritis. Mean follow-up was 11 years in the 4CA group and 18 years in the PRC group.

RESULTS

Overall, there were no differences between groups in the need for revision surgery. Complications included 6 nonunions in the 4CA group (12%), 1 infection in each group, and 11 patients who experienced radiocarpal impingement (8 4CA and 3 PRC). There was no difference in the number of patients reporting moderate or severe pain between the PRC and 4CA groups. Mean flexion-extension arc was 54° after 4CA, compared with 73° after PRC. Patients who underwent 4CA had slightly improved grip strength (65% of the opposite side) compared with those who had PRC (54%). Mean postoperative Disabilities of the Arm, Shoulder, and Hand questionnaire scores were 32 versus 19 (PRC vs 4CA) and patient-rated wrist evaluation scores were 27 versus 28 (PRC vs 4CA). Comparing radiographic arthritis, the 10-year outcome, free of moderate/severe arthritis for the PRC and 4CA groups, was 70% and 71%, respectively.

CONCLUSIONS

Both PRC and 4CA represent a good surgical option for young patients with wrist arthritis, with similar complication rates, postoperative pain levels, wrist function, and long-term outcomes free of arthrodesis. Proximal row carpectomy has improved motion and fewer complications.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Clinical outcomes of proximal row carpectomy by preoperative midcarpal joint morphological classification: Viegas type I versus type II

The midcarpal joint can be classified into two anatomical types - Viegas type I and Viegas type II - based on the absence or presence of a medial facet for the hamate on the lunate (lunohamate facet). Type I is associated with a round capitate shape, which theoretically allows better congruence with the lunate fossa of the distal radius following proximal row carpectomy (PRC). This morphological feature has never been considered as a predictive factor of clinical outcome for this surgical procedure. This study aimed to compare the clinical and radiological outcomes of the two Viegas types following PRC. A retrospective single-center study was carried out on patients who underwent PRC for wrist osteoarthritis. Minimum follow-up was 2 years. Lunate type was determined based on preoperative CT arthrography. The clinical evaluation included range of motion (ROM) and strength as well as the functional DASH, Mayo Wrist scores and a VAS for pain. The outcome of radiocapitate osteoarthritis was assessed on plain radiographs. Forty patients were reviewed with a mean follow-up of 57 months. Twenty-one Viegas type I and 19 Viegas type II were identified on preoperative CT arthrography. The etiologies included 23 SLAC wrists (12 Viegas type I, 11 type II), 8 SNAC wrists (4 Viegas type I, 4 type II), 6 cases of Kienböck's disease (3 type IIIa, 3 type IIIb with 3 Viegas type I and 3 type II), 1 Preiser's disease and 2 cases of transscaphoid perilunate dislocation of the carpus. Patients with a Viegas type I lunate had significantly greater flexion-extension ROM: 83.5° vs. 71° (P=0.04) and radial deviation: 12° vs. 7° (P=0.013) than those with Viegas type II. However, three cases of complex regional pain syndrome (CRPS) were reported in the Viegas type II group vs. zero in the Viegas type I group. There were no differences between the two groups in terms of strength, functional scores or VAS pain. The outcome of radiocapitate osteoarthritis was similar in both groups. Considering the number of CRPS cases in the Viegas type II group and similar functional results in both groups, the worse outcomes of the Viegas type II patients in terms of ROM cannot be considered as clinically relevant. This comparative study does not provide a reasonable basis for concluding that Viegas type I patients are better candidates for PRC than Viegas type II patients.

Proximal row carpectomy on manual workers: 17 patients followed for an average of 6 years

Proximal row carpectomy (PRC) is indicated for the treatment of SNAC or SLAC wrist with preservation of the midcarpal joint. Our hypothesis was that PRC is not appropriate for treating advanced wrist osteoarthritis in patients who carry out heavy manual work. Twenty-three PRCs were performed on 21 patients, 5 women and 16 men with an average age of 54 years (33-77). All patients performed manual work; 11 of them performed heavy manual work. Etiologies were: SLAC wrist in 14 cases (2 stage III, 11 stage II, and 1 stage I) and SNAC wrist in 9 cases (6 stage IIIB and 3 stage IIB). At an average 75 months' follow-up (24-153), five patients were lost to follow-up. Radiocarpal arthrodesis was performed in one patient 10 years after the PRC. In the 17 remaining patients (18 wrists), pain (VAS) averaged 2.2, with residual pain of 5. Flexion-extension range was similar to preoperative levels (67% of contralateral wrist). Wrist strength was decreased by 34% compared to preoperative. The QuickDASH score averaged 26 points and the PRWE 20 points. Radiocapitate distance decreased by 0.3mm on average with joint line narrowing in 6 patients. The carpal translation index was 0.33mm, which was unchanged relative to preoperative values. Three patients had work-related limitations that required retraining and one patient had to be reassigned. PRC preserved the preoperative range of motion and reduced pain levels. However, significant loss of strength was observed, resulting in 23% of manual workers needing retraining or reassignment.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

In vitro experimental investigation of the forces and torque acting on the scaphoid during light grasp

The aim of this study was to measure the magnitude and direction of forces and torque within osteotomized scaphoids within cadaveric wrists during grasping movement of the hand. The mechanical contributions of clinically relevant individual wrist-crossing tendon groups were investigated. Wrists of eight forearms were immobilized in the sagittal, transverse, and coronal plane on a fixation device with unhindered axial gliding. The scaphoid was osteotomized and the fragments stabilized using an interlocking nail. The nail served as a sensor for measurement of inter-fragmentary forces orthogonal and torque around the sensor axis. Thus, torque and cantilever forces were measured which originated between the fragments through co-contraction through the activity of wrist-crossing tendons. Grasping movement of the hand induced a mean maximum torque of 0.038 ± 0.051 Nm and a force of 4.01 ± 1.71 N on the scaphoid. The isolated activation of thumb tendons resulted in a torque of 9.9 E^-3 ± 7.7 E^-3 Nm and a force of 1.42 ± 0.49 N. Despite immobilization of the wrist, grasping movement of the hand caused substantial forces and torque within the osteotomized scaphoid bone in varying directions and severity among different specimens. These factors may contribute to the development of nonunions and malunions in unstable scaphoid fractures through interfragmentary micromotion. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1734-1742, 2016.

Factors associated with improved outcomes following proximal row carpectomy: a long-term outcome study of 144 patients

We conducted a review of 144 consecutive patients who underwent proximal row carpectomy from 1967 to 2010 for the diagnosis of wrist arthritis. At a mean follow-up of 13.4 years, patients experienced good pain relief with preservation (but not improvement) of wrist motion. A total of 17 patients (12%) required revision surgery at an average of 44.6 months. Improved pain, function, and survival outcomes were seen in those who underwent proximal row carpectomy after the age of 40, had a preoperative diagnosis of Kienbock's disease, who underwent a concomitant neurectomy procedure, patients who were non-labourers, and patients who underwent surgery after 1990. Although 45% of patients developed moderate to severe radiocapitate arthrosis postoperatively, these findings did not correlate with clinical outcomes or risk of revision surgery. Patients with type II lunate and type II and III capitate shapes had higher rates of postoperative radiocapitate arthrosis.

LEVEL OF EVIDENCE

III, Prognostic.

Scapholunate Advanced Collapse: Motion-Sparing Reconstructive Options

Scapholunate advanced collapse (SLAC) is a predictable pattern of degenerative wrist arthritis that develops as a result of scapholunate dissociation. The purpose of this article is to review outcomes for the various motion-sparing surgical treatments for SLAC wrist.

In vivo contact biomechanics in the trapeziometacarpal joint using finite deformation biphasic theory and mathematical modelling

The assessment of the contact biomechanics in the trapeziometacarpal (TMC) joint during functional tasks represents a relevant way to obtain a better understanding of the onset of osteoarthritis (OA). CT scans of the hand region of 20 female volunteers were taken in relaxed neutral, lateral key pinch and power grasp configuration. 3D models of the first metacarpal (MC1) and the trapezium were created. The articular area of each bone was quantified and a mathematical model was developed in Matlab to evaluate the projected contact area and stress distribution of each bone. The articular areas of the MC1 and the trapezium presented no significant difference. A slightly smaller projected contact area was calculated for the trapezium compared to the MC1. Similar amounts of stress were reported in the neutral and lateral pinch configurations. The highest stress levels were observed during power grasp. Very consistent results for high stress location on the volar/radial articular sub-region were found in the neutral and power grasp configurations. More variation was reported during lateral pinch. The mathematical model presented in this paper offers the possibility to predict contact patterns within the TMC joint based on in vivo CT images.

Surgical Treatments for Scapholunate Advanced Collapse Wrist: Kinematics and Functional Performance

PURPOSE

The purpose of this investigation was to compare kinematic motion and functional performance during 2 tasks in patients following 4-corner fusion (4CF) or proximal row carpectomy (PRC) and to compare these data with those from healthy asymptomatic individuals.

METHODS

Twenty men (10 4CFs and 10 PRCs, ages, 43-82 y) were recruited for 3-dimensional wrist motion analysis testing. Kinematic coupling (the ratio of wrist flexion/extension to radial-ulnar deviation), kinematic path length (a measure of total angle distance), clinical measures, and performance measures were collected during 2 tasks: dart throwing and hammering. For each outcome, between-group comparisons employed a 1-way analysis of variance with post hoc analysis using the Fisher least significant difference test.

RESULTS

All clinical measures (flexion-extension, radial-ulnar deviation, and grip strength) were decreased for 4CF and PRC patients compared with healthy subjects. Coupling, kinematic path length, and performance were all significantly reduced in 4CF and PRC patients compared with healthy subjects during both tasks. Reduced coupling and a shorter kinematic path length are indicative of less global and combined wrist motion. There were no differences identified in coupling patterns or performance between the surgical groups for the dart-throwing task. However, in hammering, the kinematic path length and performance (time and total strikes) were worse in 4CF than in PRC.

CONCLUSIONS

Differences in wrist kinematics and performance were identified between the groups. PRC subjects performed better on kinematic and performance variables. As expected, both groups demonstrated decreased wrist kinematic motion and functional performance compared with individuals with normal wrists. These results require confirmation and while they cannot be used to determine the benefits of one procedure over the other, they are an important step in quantifying differences in motion and function between procedures.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

Radiocapitate congruency as a predictive factor for the results of proximal row carpectomy

PURPOSE

To evaluate whether the congruency between the joint surfaces of the lunate fossa of the distal radius and the proximal capitate might be a prognostic factor for functional, clinical, or radiographic results after proximal row carpectomy (PRC).

METHODS

After reconstructing the computed tomographic arthrogram of patients with PRC, we evaluated the shape of the proximal capitate by measuring the radius of curvature of the tip of the capitate. The congruency of the future radiocapitate joint was then evaluated by the radiocapitate index in the frontal and sagittal planes. This was calculated by dividing the radius of curvature of the tip of the capitate by the mean radius of curvature of the lunate fossa. We determined the relationship between these morphological results and the functional (Disabilities of the Arm, Shoulder, and Hand [DASH] score, Mayo Wrist score, and pain relief), clinical (mobility and strength) and x-ray results (radiocapitate arthrosis).

RESULTS

A total of 27 patients were reviewed at a mean follow-up of 59 months. The shape of the proximal capitate did not affect outcomes. In the frontal plane, a better radiocapitate congruency was significantly associated with an increase in wrist flexion and better functional results for the DASH. There was a non-significant relationship between congruency and improvement of Mayo Wrist score and pain relief. In the sagittal plane, the DASH score tended to improve when congruency was better.

CONCLUSIONS

The shape of the capitate was not a prognostic factor for functional outcome after PRC. The radiocapitate index seems more relevant in predicting results at last follow-up.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Application of a three-dimensional computational wrist model to proximal row carpectomy

A three-dimensional (3D) computational model of the wrist examined the biomechanical effects of the proximal row carpectomy (PRC), a surgical treatment of certain wrist degenerative conditions but with functional consequences. Model simulations, replicating the 3D bony anatomy, soft tissue restraints, muscle loading, and applied perturbations, demonstrated quantitatively accurate responses for the decreased motions subsequent to the surgical procedure. It also yielded some knowledge of alterations in radiocarpal contact force which likely increase contact pressure as well as additional insight into the importance of the triangular fibrocartilage complex and retinacular/capsular structures for stabilizing the deficient wrist. As better understanding of the wrist joint is achieved, this model could serve as a useful clinical tool.

Osteoarthritis of the wrist

This article reviews pathogenesis and treatment of wrist osteoarthritis. Because there is no cure for osteoarthritis, treatment is directed at symptomatic relief. Surgical treatment is reserved for patients who have failed nonoperative modalities. This article reviews the surgical treatment of wrist osteoarthritis with an emphasis on selection of the appropriate procedure. Literature guiding surgical treatment with patient outcomes is reviewed.

Effect of capitate morphology on contact biomechanics after proximal row carpectomy

PURPOSE

Proximal row carpectomy (PRC) is used as a treatment for a variety of wrist pathologies to maintain motion and to improve strength and decrease pain. Several studies have looked at how PRC alters wrist characteristics, although they did not provide an explanation for the variability observed in outcomes. Studies have classified the capitate into 3 unique types: round, V-shaped, or flat. We hypothesized that these differences in morphology could affect the contact biomechanics between the radius and the capitate after PRC.

METHODS

A total of 14 cadaveric wrists underwent PRC. They were classified by capitate morphology and then loaded to 200 N in a neutral position, flexion, and extension. We measured contact area, contact pressure, and location using pressure-sensitive film in all 3 positions and compared their morphology types.

RESULTS

Nine wrists had a round-type capitate, 4 had a V-shaped capitate, and 1 had a flat capitate, which we excluded from statistical analysis. Comparing round and V-shaped types, we found no differences in contact area, pressure, or location in any wrist position For the V-shaped capitates, there was increased contact pressure in flexion and extension compared with the wrist in neutral. Center of pressure translated dorsal and radial in flexion to volar and ulnar in extension for all types.

CONCLUSIONS

When we compared V-shaped and round-type capitates, we found no significant differences in contact characteristics of the wrist after PRC. There were some differences in contact pressure for V-shaped capitates in various wrist positions.

CLINICAL RELEVANCE

Differences between round and V-shaped capitates do not appear to affect contact biomechanics after PRC. Thus, these 2 capitate shapes may not necessarily be a factor in the decision-making process to perform PRC.

Proximal row carpectomy

Proximal row carpectomy (PRC) is a motion-preserving treatment for the degenerated wrist. PRC provides painless wrist range of motion with few complications. PRC treats specifically scapholunate advanced collapse, scaphoid non-union advanced collapse, chronic perilunate dislocations, and Kienbock's disease. The best candidates are older than 35 with an intact capitate head and lunate facet of the distal radius. Proximal row carpectomy provides satisfactory postoperative wrist range of motion and grip strength with few complications, especially when there is no capitolunate arthrosis. Postoperative progressive changes at the radiocapitate articulation have been documented, yet these changes tend to remain asymptomatic.

Arthroscopic resection arthroplasty for malunited intra-articular distal radius fractures

PURPOSE

Cartilage damage of the carpals is a contraindication for corrective osteotomy of the malunited intra-articular distal radius fracture and typically is treated in the symptomatic patient with a salvage procedure. Here, we present our experience and early results with arthroscopic resection arthroplasty of the radiocarpal joint.

METHODS

We treated 10 patients (age, 17-68 y; average, 53 y) who had intra-articular malunion of the distal radius with mirror erosion on the carpals. The original fracture occurred 4 to 36 months (average, 9 mo) before our intervention. We performed arthroscopic arthrolysis and resected the offending portion of the radial malunited fragment, eliminating the stepoff and creating a smoother joint surface. Range of motion was started immediately after the operation, except in 2 patients.

RESULTS

The locations of the malunions were evenly distributed between the scaphoid fossa, the lunate fossa, or both. Stepoffs varied from 2 to 6 mm. We resected up to 60% of the entire radial articular surface to obtain a smooth surface (average, 28%; range, 20% to 60%). All patients reported immediate relief of pain and improvement in motion (particularly extension). At the latest follow-up (average, 28 mo; range, 13-42 mo), average extension improved from 24° to 54°, average grip strength improved from 47% to 89% of the contralateral wrist, average Disabilities of the Arm, Shoulder, and Hand score improved from 74 to 18, and average Patient-Rated Wrist Hand Evaluation score improved from 79 to 15.

CONCLUSIONS

The aim of the operation was to relieve patients' pain by providing a smooth, although fibrocartilaginous, surface for the carpus to glide on the radius. The follow-up was short and the results may be short-lived. However, for the younger patient, it may provide a temporary alternative to partial wrist arthrodesis with minimal morbidity, and for the less demanding patients, it may be a definitive procedure.

Long-term outcomes of proximal row carpectomy: a systematic review of the literature

Purpose Proximal row carpectomy is a well-established technique for the management of wrist arthritis; however, patient selection and long-term durability of proximal row carpectomy is still a matter of controversy. Hence, we conducted a systematic review of the English literature to determine the best evidence on long-term outcomes following proximal row carpectomy. Methods A MEDLINE search using the term "proximal row carpectomy" was performed. A total of 192 studies were identified. All studies with 10 or more years of follow-up were included in the review. Data extracted included patient demographics, indications for surgery, previous surgery, outcome assessment, and information on complications and failures. Results A total of 147 patients from six studies met the inclusion criteria and were included in the study. The majority of patients were male and involved in manual labor. There was no significant difference between the preoperative and long-term postoperative motion. The weighted mean for postoperative grip strength was 68.4% compared with the contralateral side. Disabilities of the arm, shoulder, and hand; patient-rated wrist examination; and Mayo wrist scores were comparable to those reported for four-corner arthrodesis. There were 21 failures (14.3%) requiring re-operation. Failures were not associated with a specific preoperative diagnosis but distributed among patients with Kienböck disease, scaphoid nonunion advanced collapse, and scapholunate advanced collapse arthritis. Conclusions This systematic review confirms the long-term durability of proximal row carpectomy when used for the treatment of wrist arthritis. Although radiocapitate arthritis develops over time in most patients, the clinical significance of this finding is undetermined and does not necessarily correlate with failure of proximal row carpectomy. Poorer long-term outcomes are likely to result in patients engaged in heavy manual labor, whereas better outcomes may be obtained in patients undergoing proximal row carpectomy for trauma or earlier-stage Kienböck disease.

Scaphoid excision and 4-bone arthrodesis versus proximal row carpectomy: a comparison of contact biomechanics

PURPOSE

We compare scaphoid excision and 4-bone arthrodesis (FBA) with proximal row carpectomy (PRC) in terms of contact pressure, area, and location.

METHODS

Six cadaveric forearms underwent simulated FBA with K-wires. We measured pressures in the radiocarpal joint with Fuji contact film after we applied a 200-N load via the wrist tendons with the wrist in neutral, flexion, and extension. We repeated the experiment after excising the lunate and triquetrum, to create a PRC in the same specimens.

RESULTS

Contact pressure in the PRC wrist was significantly greater, by 25%, compared with the FBA wrist for all wrist positions. The PRC wrist had a significantly smaller contact area, by 43%, compared with the FBA wrist. In the FBA wrist, lunate contact was more dorsal in flexion but more volar in extension. In the PRC wrist, capitate contact was more dorsal and radial in flexion, whereas the contact was more volar and ulnar in extension. Comparing contact location, FBA contact was significantly more ulnar than PRC contact in wrist flexion. We found no significant difference in contact translation (the distance between the contact locations in the positions of wrist flexion and extension) for the lunate in FBA or the capitate in PRC.

CONCLUSIONS

The FBA wrist has significantly lower contact pressure (P < .001), greater contact area (P < .001), and equal contact translation compared with the PRC wrist. These qualities may make FBA less susceptible to degeneration over time. By advancing our understanding of the biomechanics of both wrist procedures, we may better tailor them to the individual patient.

CLINICAL RELEVANCE

Current biomechanical evidence is lacking for common motion-preserving procedures for wrist arthritis. Comparing contact pressure, area, and location provides a biomechanical basis of our clinical understanding of these surgeries.

The biomechanical effects of a deepened articular cavity during dynamic motion of the wrist joint

BACKGROUND

A deepened articular cavity of the distal radius due to a metaphyseal comminution zone is associated with early osteoarthritis and reduced joint motion. As this deformity has not been investigated biomechanically, the purpose of this study was to evaluate the effects of a deepened articular cavity on contact biomechanics and motion range in a dynamic biomechanical setting.

METHODS

Six fresh frozen cadaver forearms were tested in a force controlled test bench during dynamic flexion and extension and intact mean contact pressure and contact area as well as range of motion were evaluated. Malunion was then simulated and intraarticular as well as motion data were obtained. Intact and malunion data were compared for the scaphoid and lunate facet and the total radial joint surface.

FINDINGS

Due to malunion simulation, cavity depth increased significantly. Motion decreased significantly to 54-69% when compared to the intact state. Malunion simulation led to a significant decrease of contact area in maximum extension for all locations (by ~50%). In maximum flexion and neutral position, contact area decrease was significant for the scaphoid fossa (by 51-54%) and the total radial joint surface (by 47-50%). Contact pressure showed a significant increase in maximum extension in the scaphoid fossa (by 129%).

INTERPRETATION

Already a small cavity increase led to significant alterations in contact biomechanics of the radiocarpal joint and to a significant range of motion decrease. This could be the biomechanical cause for degenerative changes after the investigated type of malunion. We think that restoration of the normal distal radius shape can minimize osteoarthritis risk post trauma and improve radiocarpal motion.

Proximal row carpectomy with capitate osteochondral autograft transplantation

Proximal row carpectomy (PRC) is an effective treatment option for degenerative or posttraumatic osteoarthritis of the wrist in conditions such as scapholunate advanced collapse, scaphoid nonunion advanced collapse, Kienbock disease, and chronic fracture dislocations of the carpus. PRC involves excision of the scaphoid, lunate, and triquetrum, and relies on the articulation of the remaining capitate from the distal row to articulate with the lunate fossa. PRC offers the potential advantage of greater range of motion, technical ease, and decreased immobilization, and eliminates specific complications found with other motion-preserving procedures such as nonunion, hardware irritation, and impingement. An established relative contraindication for PRC is the presence of advanced capitolunate arthritis. Many authors have offered modifications of the traditional PRC procedure to account for the presence of capitate arthritis. A PRC technique utilizing an osteochondral autograft, from the carpal bank of excised bones, for transfer to the capitate defect is described.

Long-term outcomes of proximal row carpectomy: a minimum of 15-year follow-up

INTRODUCTION

Proximal row carpectomy (PRC) is a popular procedure for the treatment of wrist arthritis; however, the long-term clinical outcomes of this procedure are not well-characterized. The purpose of this study was to evaluate long-term results with PRC and to identify factors that may improve clinical outcomes.

METHODS

A retrospective study was performed on all patients who underwent proximal row carpectomy between January 1967 and January 1992. Medical records and available radiographs were reviewed. The Disabilities of the Arm, Shoulder and Hand, and Patient Rated Wrist Exam, as well as hand motion diagrams were sent to all surviving patients. The contralateral extremity was used as a control. Data was analyzed using multivariant analysis and a Student's t test.

RESULTS

Eighty-one patients underwent PRC. Average age at the time of surgery was 41 years. Average follow-up was 19.8 years. Sixty-one patients responded to the questionnaires. On final follow-up, wrist motion and grip strength were not significantly different from preoperative values. Radiographic follow-up beyond 2 years revealed joint narrowing and arthritic changes within the radiocapitate joint. Forty-six patients (74%) were not satisfied with the results of their surgery due to persistent pain or inability to return to previous occupational activities. Fifty-two patients required daily pain medication for wrist pain. Twelve patients had undergone a wrist arthrodesis.

CONCLUSIONS

Post-operative motion and grip strength values following PRC appear to remain stable over time. Surgical failure rates with conversion to wrist fusion occurred early within the post-operative follow-up. Many patients continued to complain of pain requiring daily medication and were unable to return to manual labor type jobs. The results of this study suggest that long-term patient satisfaction following PRC can be poor and the surgeon may wish to consider alternative treatment options for younger patients and those with high-demand jobs.

Proximal row carpectomy with allograft scaffold interposition arthroplasty

The authors present a solution for motion preservation in severe wrist arthritis with intercarpal involvement. Acellular dermal allograft is used as an interposition arthroplasty in these situations, rather than local tissue flaps such as previously described. Proximal row carpectomy has been shown to be one of the most successful procedures to correct chronic destructive arthritis in the wrist, keeping useful motion. Traditionally, a contraindication for proximal row carpectomy includes an arthritis that invades the lunate-capitate joint. The authors describe a technique to extend the traditional indications by covering the eroded articular surfaces with dermal allograft scaffold.

Measurement of intraarticular wrist joint biomechanics with a force controlled system

Pathologies of the wrist, such as fractures or instabilities, can lead to alterations in joint biomechanics. Accurate treatment of these pathologies is a frequent challenge for the surgeon. For biomechanical investigations, a test-setup that applies physiological loading of the wrist joint is necessary. A force controlled test-bench with agonistic and antagonistic muscle forces was built to move six fresh frozen human upper extremities through flexion and extension of the wrist joint. Tendon forces, range of motion, intraarticular contact area and contact pressure of the lunate and scaphoid facet as well as tendon excursion were investigated and compared with the current literature. During wrist motion the extensors exerted double the force of the flexors. Capsulotomy and sensor insertion decreased the range of motion from 63.4° (SD 14.1) to 45.9° (SD 23.7). The ratio of force transmitted through the radius and ulna was 77:23 and pressure distribution between the scaphoid and lunate facet showed a 70:30 relationship. The obtained data indicate a good agreement with the available literature. Therefore, the force controlled test-bench in combination with intraarticular radiocarpal measurements can be used to investigate the influence of wrist pathologies on joint biomechanics.

Effects of proximal row carpectomy on wrist biomechanics: a cadaveric study

BACKGROUND

Many studies show good clinical results after proximal row carpectomy. Some biomechanical consequences are documented, but to our knowledge muscle moment arm variations have not previously been quantified.

METHODS

In five fresh-frozen wrist, kinematics and tendon excursions were measured using a 3D electrogoniometer and Linear Variable Differential Transformers (SOLARTRON Inc., AMETEK Advanced Measurement Technology, Inc, 801 South Illinois Avenue, Oak Ridge, TN 37831-2011, USA), respectively, in three conditions: intact wrist, after posterior capsulotomy and after proximal row carpectomy. Mean pivot point, defined as the point whose sum of the squared distances to the helical axes is minimum, wrist range of motion and mean moment arms were measured during dorso-palmar flexion, radioulnar deviation and circumduction movements.

FINDINGS

No alteration of the range of motion was observed. On the other hand, the mean pivot point shifted proximally (6.8-9.1mm) after proximal row carpectomy (p<0.05) for all motions tested and most muscle moment arms decreased significantly after proximal row carpectomy.

INTERPRETATION

The results of this study allow a better understanding of the biomechanical effects of this procedure. The important moment arm reduction and pivot point displacement suggest modifications of joint biomechanical parameters which could influence the functional outcome of PRC.

Arthroscopic proximal row carpectomy

PURPOSE

Proximal row carpectomy is an effective procedure for treating a variety of wrist pathologies. To date, all outcome studies have reported on the results of an open procedure, with a dorsal capsulotomy. We present our technique and early results of arthroscopic proximal row carpectomy.

METHODS

A total of 17 consecutive patients (10 men and 7 women) underwent arthroscopic proximal row carpectomy. After routine arthroscopy, the proximal carpal row was removed with an arthroscopic bur, with care being taken to protect the articular cartilage of the head of the capitate and the lunate fossa. The average time of the procedure was 70 minutes (range, 34-110 min). Range of motion exercise was initiated 2 days postoperatively. We assessed clinical follow-up objectively by evaluating range of motion and grip strength. We assessed subjective outcomes with the Disabilities of the Arm, Shoulder, and Hand questionnaire and with a patient-centered questionnaire assessing satisfaction, return to prior employment, and pain.

RESULTS

A total of 16 patients were available, with an average follow-up of 24 months (range, 12-48 mo). There were no complications, no revisions were required, and no arthroscopic procedure was converted to open technique. At final follow-up, the average wrist flexion-extension arc was 80% of the contralateral side, and grip strength averaged 81% of the contralateral side. The mean Disabilities of the Arm, Shoulder, and Hand score was 21. All 16 patients rated themselves as satisfied or very satisfied with the procedure. Eleven patients had no work restrictions and 13 were able to return to previous employment. Ten patients rated themselves as having mild or no pain.

CONCLUSIONS

Arthroscopic proximal row carpectomy appears to be a safe, effective, and reliable procedure for a variety of wrist conditions, and it allows for rapid mobilization of the wrist compared with the open procedure. Range of motion and grip strength compare favorably with existing values in the literature for the open technique.

The outcome of scaphoid excision and four-corner arthrodesis for advanced carpal collapse at a minimum of ten years

PURPOSE

Scaphoid excision and 4-corner arthrodesis is a salvage option for patients with advanced carpal collapse. This study aims to compare the clinical outcomes of 4-corner arthrodesis (FCA) at one year, 2 years, and a minimum of 10 years.

METHODS

A cohort study was performed of patients having scaphoid excision and FCA procedure by a single surgeon. Thirty-one of 35 recruited were followed up for 10 years. The mean patient age was 47 years. All patients had scaphoid excision and FCA, using bone graft and 3M Shapiro staples (3M, St Paul, MN). Patients were followed up prospectively at one year, 2 years, and a minimum of 10 years after surgery by an independent observer. Three patients were lost to follow-up between the 2-year and 10-year assessments because they were untraceable, and one patient died at 7 years, without any further intervention. Before surgery, pain scores measured with a visual analog scale, range of wrist movement, grip and pinch strength, and scores from a self-assessment functional questionnaire were recorded prospectively. These measures were repeated at each time point, in addition to patient satisfaction scores measured on a visual analog scale.

RESULTS

The pain scores decreased from a median preoperative score of 6/10 to 0/10 at one year. Grip strength did not change significantly. Wrist flexion decreased significantly after surgery, by an average of 22%. The average patient-reported satisfaction score was 8/10. There was no significant change in pain, wrist function, satisfaction, or arc of motion between one and 10 years. Two of 35 patients recruited had gone on to a total wrist arthrodesis for ongoing pain.

CONCLUSIONS

The outcome of scaphoid excision and 4-corner arthrodesis is favorable at one year and does not deteriorate significantly between one and 10 years. There is a low rate of conversion to total wrist arthrodesis. Pain scores are reduced at the cost of reduced wrist flexion.