In Vivo Kinematics of the Thumb Carpometacarpal Joint During Three Isometric Functional Tasks

Background

The thumb carpometacarpal (CMC) joint is often affected by osteoarthritis—a mechanically mediated disease. Pathomechanics of the CMC joint, however, are not thoroughly understood due to a paucity of in vivo data.

Questions/purposes

We documented normal, in vivo CMC joint kinematics during isometric functional tasks. We hypothesized there would be motion of the CMC joint during these tasks and that this motion would differ with sex and age group. We also sought to determine whether the rotations at the CMC joint were coupled and whether the trapezium moved with respect to the third metacarpal.

Methods

Forty-six asymptomatic subjects were CT-scanned in a neutral position and during three functional tasks (key pinch, jar grasp, jar twist), in an unloaded and a loaded position. Kinematics of the first metacarpal, third metacarpal, and the trapezium were then computed.

Results

Significant motion was identified in the CMC joint during all tasks. Sex did not have an effect on CMC joint kinematics. Motion patterns differed with age group, but these differences were not systematic across the tasks. Rotation at the CMC joint was generally coupled and posture of the trapezium relative to the third metacarpal changed significantly with thumb position.

Conclusions

The healthy CMC joint is relatively stable during key pinch, jar grasp, and jar twist tasks, despite sex and age group.

Clinical Relevance

Our findings indicate that directionally coupled motion patterns in the CMC joint, which lead to a specific loading profile, are similar in men and women. These patterns, in addition to other, nonkinematic influences, especially in the female population, may contribute to the pathomechanics of the osteoarthritic joint.     

Verletzungen des Sattelgelenks und posttraumatische Rhizarthrose

Background

Precise function of the hand is crucially characterized by opposition movement of the thumb, only possible because of the functional anatomy of the first carpometacarpal joint. High functional demands to this joint consequently lead to the highest rate of osteoarthritis of the hand joints and loss of function. Carpometacarpal (CMC) osteoarthritis of the thumb is rarely seen in posttraumatic cases. It can be caused by fractures involving the joint surfaces of both, the trapezium or the first metacarpal, whereas dislocations of the carpometacarpal joint itself only occasionly lead to osteoarthritis.

Objectives

Identification and compilation of current concepts in diagnosis and therapy of posttraumatic carpometacarpal osteoarthritis of the thumb.

Methods

Selective PubMed and Cochrane review, data obtained from own patient investigations and author’s experiences were used.

Results

Adequate treatment of the injury will minimize the risk for future malfunction. In early stages, arthroscopy is a valuable method for the diagnosis and treatment of posttraumatic rhizarthrosis. For all stages, a multitude of operative procedures are described and being used but yet not finally assessed for effectiveness. Advanced osteoarthritis of the first CMC joint is widely treated by trapeziectomy, which is suitable for most patients, and considered as gold standard. Additional procedures like suspension, interposition or k-wire transfixation do not provide any significant advantage and lead to comparable results. It is advisable to treat hyperextension of the metacarpophalangeal joint of the thumb at any stage of CMC osteoarthritis.     

Does Arthroscopic Débridement With or Without Interposition Material Address Carpometacarpal Arthritis?

Background

Thumb carpometacarpal (CMC) joint arthritis is a common problem in clinical practice with a variety of treatment options. Arthroscopic procedures can preserve all or part of the trapezium in the setting of treatment of basilar joint arthritis, and such procedures (even without stabilization or ligament reconstruction) have high reported success rates. However, little is documented about the limitations of these procedures in terms of patient selection, the optimal type of interposition, if any, and rehabilitation.

Questions/purposes

A systematic review was performed to determine the influence of (1) interposition material (manufactured, biological, or none); and (2) patient-related factors (including metacarpophalangeal joint hyperextension, ligamentous laxity, and severity of arthritis) on pain, functional scores, and postoperative complications unique to each approach.

Methods

A systematic review of the English language literature regarding thumb basilar joint arthritis and arthroscopic partial trapeziectomy or débridement was performed. Those procedures including ligament reconstruction or stabilization were excluded.

Results

Biological materials and no interposition were both associated with satisfactory improvement and low rates of complications; complication rates with synthetic materials were higher. Eaton Stages I to III were treated successfully with this technique. The effect of scaphotrapeziotrapezoid (STT) changes was variably described across series. In most series, metacarpophalangeal hyperextension did not seem to have an adverse effect on outcomes, although these patients were excluded in some series.

Conclusions

Arthroscopic débridement with or without interposition can be used for treatment of Eaton Stages I to III CMC osteoarthritis with satisfactory outcomes. Some series suggest satisfactory outcomes in the setting of STT changes and metacarpophalangeal hyperextension.     

Intra- and Interobserver Reliability of the Eaton Classification for Trapeziometacarpal Arthritis: A Systematic Review

Background

Trapeziometacarpal, or thumb carpometacarpal (CMC), arthritis is a common problem with a variety of treatment options. Although widely used, the Eaton radiographic staging system for CMC arthritis is of questionable clinical utility, as disease severity does not predictably correlate with symptoms or treatment recommendations. A possible reason for this is that the classification itself may not be reliable, but the literature on this has not, to our knowledge, been systematically reviewed.

Questions/purposes

We therefore performed a systematic review to determine the intra- and interobserver reliability of the Eaton staging system.

Methods

We systematically reviewed English-language studies published between 1973 and 2013 to assess the degree of intra- and interobserver reliability of the Eaton classification for determining the stage of trapeziometacarpal joint arthritis and pantrapezial arthritis based on plain radiographic imaging. Search engines included: PubMed, Scopus^®, and CINAHL. Four studies, which included a total of 163 patients, met our inclusion criteria and were evaluated. The level of evidence of the studies included in this analysis was determined using the Oxford Centre for Evidence Based Medicine Levels of Evidence Classification by two independent observers.

Results

A limited number of studies have been performed to assess intra- and interobserver reliability of the Eaton classification system. The four studies included were determined to be Level 3b. These studies collectively indicate that the Eaton classification demonstrates poor to fair interobserver reliability (kappa values: 0.11–0.56) and fair to moderate intraobserver reliability (kappa values: 0.54–0.657).

Conclusions

Review of the literature demonstrates that radiographs assist in the assessment of CMC joint disease, but there is not a reliable system for classification of disease severity. Currently, diagnosis and treatment of thumb CMC arthritis are based on the surgeon’s qualitative assessment combining history, physical examination, and radiographic evaluation. Inconsistent agreement using the current common radiographic classification system suggests a need for better radiographic tools to quantify disease severity.     

The 2014 ABJS Nicolas Andry Award: The Puzzle of the Thumb: Mobility,Stability, and Demands in Opposition

Background

The paradoxical demands of stability and mobility reflect the purpose and function of the human thumb. Its functional importance is underscored when a thumb is congenitally absent, injured, or afflicted with degenerative arthritis. Prevailing literature and teaching implicate the unique shape of the thumb carpometacarpal (CMC) joint, as well as its ligament support, applied forces, and repetitive motion, as culprits causing osteoarthritis (OA). Sex, ethnicity, and occupation may predispose individuals to OA.

Questions/purposes

What evidence links ligament structure, forces, and motion to progressive CMC disease? Specifically: (1) Do unique attributes of the bony and ligamentous anatomy contribute to OA? (2) Can discrete joint load patterns be established that contribute to OA? And (3) can thumb motion that characterizes OA be measured at the fine and gross level?

Methods

We addressed the morphology, load, and movement of the human thumb, emphasizing the CMC joint in normal and arthritic states. We present comparative anatomy, gross dissections, microscopic analysis, multimodal imaging, and live-subject kinematic studies to support or challenge the current understanding of the thumb CMC joint and its predisposition to disease.

Results

The current evidence suggests structural differences and loading characteristics predispose the thumb CMC to joint degeneration, especially related to volar or central wear. The patterns of degeneration, however, are not consistently identified, suggesting influences beyond inherent anatomy, repetitive load, and abnormal motion.

Conclusions

Additional studies to define patterns of normal use and wear will provide data to better characterize CMC OA and opportunities for tailored treatment, including prevention, delay of progression, and joint arthroplasty.

Electronic supplementary material

The online version of this article (doi:10.1007/s11999-014-3901-6) contains supplementary material, which is available to authorized users.     

In Vivo Pilot Study Evaluating the Thumb Carpometacarpal Joint During Circumduction

Background

Analysis of arthrokinematics may have clinical use in the diagnosis of dynamic instability of the thumb and wrist. Recent technological advances allow noninvasive, high-resolution imaging of skeletal (thumb and carpal bones) structures during motion.

Questions/purposes

The primary purpose of this study is to define the arthrokinematics, estimated joint contact patterns, and distribution ratios of the carpometacarpal joint of the thumb using four-dimensional CT (three-dimensional CT + time) and registration algorithms. The second purpose is to validate the accuracy of the approach.

Methods

Four-dimensional CT scans were obtained using a nongated sequential scanning technique. Eighteen image volumes were reconstructed over a 2-second cycle during thumb circumduction in one healthy volunteer. Using a registration algorithm, serial thumb motions as well as estimated joint contact areas were quantified. To evaluate the accuracy of our approach, one cadaveric hand was used.

Results

During circumduction, the ranges of motion of the thumb carpometacarpal joint were: flexion-extension, 27.3°; adduction-abduction, 66.9°; and pronation-supination, 10°. The magnitude of the translation of the center of the estimated joint contact area of the metacarpal was 4.1, 4.0, 1.0, and 1.5 mm when moving from the initial key pinch position to adduction, adduction to palmar abduction, palmar abduction to opposition, and opposition to the initial key pinch position, respectively. The maximum estimated contact area on the trapezium and on the metacarpal was in palmar abduction; the minimum was in adduction. Dominant central-volar contact patterns were observed on both the trapezium and the metacarpal bone except in adduction. This analysis approach had an average rotational error of less than 1°.

Conclusions

During circumduction, the estimated joint contact area was concentrated on the central-volar regions of both the trapezium and the metacarpal bones except when the thumb was adducted.

Clinical Relevance

This tool provides quantification of estimated joint contact areas throughout joint motion under physiological dynamic loading conditions; this tool may, in future studies, help to clarify some of the ways that joint mechanics might or might not predispose patients to arthritis.     

What Is the Impact of Comorbidities on Self-rated Hand Function in Patients With Symptomatic Trapeziometacarpal Arthritis?

Background

The thumb trapeziometacarpal joint is one of the most common sites of arthritic degeneration prompting specialty care. Surgical treatment algorithms are based on radiographic arthritic progression. However, the pain and disability attributable to trapeziometacarpal arthritis do not correlate with arthritic stage, and depression has independently predicted poorer self-rated hand function both at baseline and after treatment in patients’ atraumatic hand conditions.

Questions/purposes

(1) Does thumb trapeziometacarpal osteoarthritis impact both self-perceived general health and hand function? (2) Do depression and other comorbid conditions differentially impact patient-rated hand function based on the presence or absence of symptomatic trapeziometacarpal arthritis? (3) How do disease-specific, patient demographics and comorbid conditions impact self-reported hand function in patients with trapeziometacarpal osteoarthritis?

Methods

This cross-sectional study compared patients with symptomatic trapeziometacarpal osteoarthritis (n = 47) with matched control subjects without a symptomatic hand condition (n = 47). All participants self-reported medical (including depression) and musculoskeletal comorbidities and completed the SF-36 and the Michigan Hand Questionnaire (MHQ). Bivariate statistical analyses contrasted the patients with trapeziometacarpal osteoarthritis to control subjects. Linear regression modeling determined the impact of subject demographic data, comorbidity burden, and examination findings on total MHQ scores in patients with trapeziometacarpal arthritis.

Results

Patients with scored trapeziometacarpal osteoarthritis indicated poorer perceived general health on the SF-36 categories of limitations resulting from physical health (52 ± 29 versus 71 ± 31, mean difference 19 [95% confidence interval {CI}, 7–31], p = 0.003) and limitations resulting from emotional problems (50 ± 27 versus 67 ± 50, mean difference 17 [95% CI, 3–33], p = 0.022) compared with control subjects. Self-reported depression was associated with worse hand function (total MHQ score) in patients with trapeziometacarpal arthritis (69 ± 20 versus 49 ± 22: mean difference −20 [95% CI, −5 to−36], p = 0.012) but not in control patients (90 ± 13 versus 84 ± 20: mean difference −5 [95% CI, −8 to 19], p = 0.404). In multivariate modeling, depression (β −20, [95% CI, −5 to −34], p = 0.009) and upper extremity comorbidities (β −25, [95% CI, −10 to −40], p = 0.002) were both associated with reduced total MHQ scores in patients with trapeziometacarpal osteoarthritis, and those factors accounted for 34% of the variance in the MHQ score.

Conclusions

When interpreting patient-rated hand disability in patients presenting with symptomatic trapeziometacarpal osteoarthritis, scores should be interpreted after accounting for the presence of depression and upper extremity comorbidities.

Level of Evidence

Level III, prognostic study.     

Treatment of osteoarthritis of the first carpometacarpal joint by resection–suspension–interposition arthoplasty using the split abductor pollicis longus tendon

Objective

Reduction of pain and gain of functionality in symptomatic osteoarthritis of the first carpometacarpal joint.

Indications

Idiopathic, rheumatic, or posttraumatic osteoarthritis of the first carpometacarpal joint.

Relative contraindications

Poor general condition, poor condition of the hand’s soft tissue/skin, chronic regional pain syndrome, current or recent infections of the hand, heavy manual labor (decision on a by-case basis).

Surgical technique

Supine position, hand pronated or slightly tilted. Upper arm tourniquet (Esmarch’s method). Loupe magnification. Incision over the first extensor compartment. Exposure and incision of the thumb’s basal joint. Resection of the trapezium. Exposure of the abductor pollicis longus (APL) tendon. Longitudinal split of the tendon harvesting the distally based ulnar part of the tendon. The split APL tendon is wrapped around the flexor carpi radialis (FCR) muscle tendon, suturing it to the tendon and back to itself. The rest of the split APL tendon is placed into the gap between the scaphoid and the first metacarpal bone, which is followed by wound closure.

Postoperative management

Plaster cast (thumb abduction splint) for 4 weeks. Stable commercially available wrist brace for at least 2 more weeks.

Results

There were no significant differences between the FCR arthroplasty (Epping’s method) and the APL arthroplasty (Wulle’s technique) regarding pain (visual analog scale), disability/usability (DASH score), or range of motion. Patients who had undergone APL arthroplasty showed significantly better grip and pinch strength. Furthermore, the operating time was significantly shorter and scars were significantly smaller in APL arthroplasty.     

Basal joint osteoarthritis of the thumb: trapeziectomy, with or without tendon interposition, or total joint arthroplasty? A prospective study

Background

There is no consensus in the literature concerning the choice of surgical procedure for thumb basal joint—trapeziometacarpal joint—osteoarthritis.

Method

Three treatments for osteoarthritis of the trapeziometacarpal joint of the thumb were compared: trapeziectomy (N = 22), trapeziectomy with ligament reconstruction and tendon interposition (LRTI) (N = 34) and a total cemented joint arthroplasty (N = 40). The mean follow-up was, respectively, 34, 26 and 26 months.

Results

There were no differences in outcome concerning pain, function and patient’s satisfaction. The DASH score demonstrated less disability in arthroplasties, but statistical significance was not reached. All patients improved in force and range of motion. The keypinch force correlated with the loss of height of the thumb. In the arthroplasty group, 40% of radiological loosening was seen.

Conclusion

Although the outcome of the three procedures was not significantly different, trapeziectomy scored the lowest in all parameters when compared with the LRTI patients. Arthroplasties were better but the high incidence of loosening is frightening for the future.     

Long-term follow-up of first metacarpal extension osteotomy for early CMC arthritis

Background

The purpose of this study was to evaluate long-term outcomes of first metacarpal extension osteotomy for early trapeziometacarpal arthritis.

Methods

We retrospectively reviewed 13 patients who underwent first metacarpal extension osteotomy at our institution between 1996 and 2005 and obtained subjective and objective outcome data.

Results

Mean follow-up was 9.9 years (range 6 to 14 years). Ten of the 13 patients (77 %) were either satisfied or very satisfied with their results. Mean pain level was 2.00 on a scale of 1 (nonexistent) to 7 (unbearable). Mean QuickDASH score was 24.17, with a median score of 9.09. Mean pinch strength was 13.1 lbs compared to 12.8 lbs in the nonoperative extremity. Mean radial abduction of the thumb was 45.5° which was equal to the nonoperative extremity. Of the eight patients who agreed to repeat radiographs, five had no progression of degenerative changes compared to pre-op radiographs.

Conclusions

Based on subjective and objective follow-up data, first metacarpal extension osteotomy can provide good long-term results in terms of patient satisfaction, pain relief, and upper extremity function. It is a reasonable alternative to ligament reconstruction in patients with early-stage trapeziometacarpal arthritis.     

Thumb carpal metacarpal arthritis

The thumb carpometacarpal (CMC) joint is the most common site of surgical reconstruction for osteoarthritis in the upper extremity. In patients older than age 75 years, thumb CMC osteoarthritis has a radiographic prevalence of 25% in men and 40% in women. The thumb CMC joint obtains its stability primarily through ligamentous support. A diagnosis of thumb CMC arthritis is based on symptoms of localized pain, tenderness and instability on physical examination, and radiographic evaluation. A reproducible radiographic classification for disease severity is based on the four-stage system described by Eaton. Nonsurgical treatment options include hand therapy, splinting, and injection. Surgical treatment is tailored to the extent of arthritic involvement and may include ligament reconstruction, metacarpal extension osteotomy, arthroscopic partial trapeziectomy, implant arthroplasty, and trapeziectomy with or without ligament reconstruction and tendon interposition.     

A retrospective multicenter study of the Artelon? carpometacarpal joint implant

Background

This study aims to evaluate patient outcomes associated with use of the Artelon® Spacer for the treatment of arthritis of the carpometacarpal joint (CMCJ) of the thumb.

Methods

Patients with Eaton stage I, II, or III carpometacarpal (CMC) joint arthritis and disabling pain that had failed conservative treatment were evaluated at 12, 36, and 48 months postsurgery for changes in pinch, patient satisfaction, pain, range of motion, grip strength, grind test, operative time, and X-ray evidence of subsidence.

Results

Complete data was available for 46 subjects and 49 thumbs. A statistically significant improvement in pain when subjected to a first CMC joint grind test, CMCJ stability and patient perception of hand and wrist function following implant insertion was seen. Patient-oriented outcomes showed statistically significant improvement in the Disabilities of the Arm, Shoulder, and Hand; pain; pinch and grip strength; and range of motion. X-ray analysis revealed that none of the distributions of measures of osteophytes, subluxation, and joint space narrowing showed statistically significant change. Bone erosion/remodeling changes of the first metacarpal were statistically significant.

Conclusions

At a follow-up period of 4 years, patients had measured improvement as well as positive self-reported functional improvements following Artelon® implant insertion for the treatment of arthritis of the thumb CMCJ.     

MCP arthrodesis using an intramedullary interlocking device

Background

A variety of metacarpophalangeal joint (MCPJ) arthrodesis techniques have been described for the treatment of symptomatic arthritis and instability of the thumb MCPJ including K wire fixation, tension-band arthrodesis, plate fixation, intramedullary screw, and other intramedullary devices. This study presents a retrospective review of one surgeon's initial series of patients undergoing thumb MCP arthrodesis using an intramedullary compression device with a fixed angle of 25°.

Methods

A retrospective chart and radiographic review of patients treated for thumb MCP arthrodesis using the intramedullary device was performed. Final radiographs were evaluated for arthrodesis angle, bony fusion, and implant fixation. Any complication found during surgery or the follow-up period was noted.

Results

In this study, 17 patients were reviewed. Indications for surgery were osteoarthritis (five patients), rheumatoid arthritis (three patients), MCP instability alone (seven patients), and post-traumatic conditions (two patients). Of these, 12 patients had a simultaneous trapeziometacarpal (TMC) soft tissue arthroplasty. Mean follow-up was 4.9 months. All 17 patients had clinical and radiographic evidence of fusion at an average of 7.9 weeks, with an average fusion angle of 24.4°. There were no hardware complications, no infections, no revisions, and no indications for hardware removal.

Discussion

Our study results indicate the technique promotes rapid union at a precise angle, provides strong fixation that does not require prolonged immobilization, does not cause hardware irritation, and can be used in conjunction with other procedures including TMC arthroplasty when MCP arthrodesis is indicated for joint instability.     

Comparative Evaluation of Surgical Procedures with Clinical Equipoise: the Unique Perspective of Our Hand Therapy Colleagues

Background

There are several accepted surgical treatment options available for carpal tunnel syndrome, thumb carpometacarpal joint (CMC), osteoarthritis (OA), and wrist degenerative joint disease.

Questions/Purposes

We sought to obtain the views and preferences from a cohort of certified hand therapists (CHT) and hypothesized that this source may identify differences in procedures that are otherwise widely believed to have clinical equipoise.

Methods

Five hundred twelve CHTs were surveyed regarding their experience, volume, and referral base along with their subjective assessments and preferences regarding open versus endoscopic carpal tunnel release (CTR), various surgical procedures for CMC OA, and proximal row carpectomy (PRC) versus 4-corner fusion (4-CF).

Results

The average CHT surveyed had 15.2 years experience and had a referral base of 7.7 different hand surgeons. Twenty-seven percent of respondents perceived superior pain control and incisional tenderness following open CTR compared to that of endoscopic CTR. However, 68% of CHTs would elect to undergo an open CTR themselves. There was no clear consensus for the optimal reconstructive technique for thumb CMC OA. As compared to that of 4-CF, PRC was thought to result in superior pain control (34 versus 22%), motion (43 versus 18%), and earlier discharge from therapy (32 versus 19%); however, 53% of respondents would prefer a 4-CF for themselves.

Conclusions

Hand therapists are intimately involved in the care of surgical patients and provide an educated and unique source for evaluating postoperative outcomes.

     

Widespread pressure pain hypersensitivity in elderly subjects with unilateral thumb carpometacarpal osteoarthritis

Background

Widespread pressure hypersensitivity is one of the signs that characterize central pain sensitization in subjects with knee and hip osteoarthritis (OA). The purpose of this study was to evaluate whether widespread pressure pain hyperalgesia is a feature of individuals with unilateral symptomatic thumb carpometacarpal (CMC) OA.

Methods

A total of 16 patients with unilateral symptomatic thumb CMC OA and 16 healthy sex- and age-matched controls were recruited. Pressure pain thresholds (PPTs) were assessed bilaterally over the first CMC joint; the C5–C6 zygapophyseal joint; the median, ulnar, and radial nerves; and tibialis anterior muscle. Grip and key strength, intensity of pain, and function QuickDASH were also measured.

Results

The analyses showed that patients with thumb CMC OA present bilaterally decreased PPTs over the first CMC joint, the C5–C6 zygapophyseal joint, and the tibialis anterior, median, ulnar and radial nerve as compared to controls (all, P < 0.01). Patients with thumb CMC OA also exhibited a bilateral reduction in pinch and grip strength than controls (P < 0.05). A significant correlation was found between PPT over the radial nerve and QuickDASH (r = 0.546, P = 0.029).

Conclusion

This study revealed bilateral widespread pressure pain hypersensitivity in individuals with unilateral symptomatic thumb CMC OA, suggesting that central pain processing mechanisms might be a feature of this pain population. These results should be taken into consideration when addressing future treatment approaches.     

Possibility of the hamatum carpometacarpal joint as a new joint donor site for interphalangeal joint restoration

Objective

This research investigates the anatomic basis for the repair and reconstruction of hand joints using transposition of the carpometacarpal (CMC) joint of the hamatum.

Methods

The morphology and structure of the CMC joints of the hamatum and the base joints of the middle phalanx were observed on 22 freshly frozen wrist specimens at Shanghai 6th People’s Hospital Research Institute of Microsurgery. The volar dorsal dia, radioulnar dia, depth of concave, and area of the joints were measured. Data were obtained through statistical analysis, and the resemblance of joints was compared in terms of morphology, structure, area, length, and diameter.

Results

The radioulnar dia of the CMC joints of the hamatum (13.54 ± 1.15 mm) did not exhibit any evident differences in the middle phalanx of the forefinger, middle finger, and ring finger, and in the distal phalanx of the thumb. The volar dorsal dia of the CMC joints of the hamatum (10.71 ± 0.93 mm) exhibited an evident difference in the middle phalanx of the ring finger. In all fingers, the depth of the ulnar and radial concave of the CMC joints of the hamatum (1.30 ± 0.08 and 0.95 ± 0.05 mm, respectively) and the area of the CMC joints of the hamatum (139.89 ± 5.44 mm²) showed an evident difference.

Conclusion

The CMC joint of the hamatum could be considered a new and viable joint donor site that could be used to repair and reconstruct the base joints of the middle phalanx.     

Carpal Tunnel Syndrome Impairs Thumb Opposition and Circumduction Motion

Background

Carpal tunnel syndrome is associated with sensory and motor impairments resulting from the compressed and malfunctioning median nerve. The thumb is critical to hand function, yet the pathokinematics of the thumb associated with carpal tunnel syndrome are not well understood.

Questions/purposes

The purpose of this study was to evaluate thumb motion abnormalities associated with carpal tunnel syndrome. We hypothesized that the ranges of translational and angular motion of the thumb would be reduced as a result of carpal tunnel syndrome.

Methods

Eleven patients with carpal tunnel syndrome and 11 healthy control subjects voluntarily participated in this study. Translational and angular kinematics of the thumb were obtained using marker-based video motion analysis during thumb opposition and circumduction movements.

Results

Motion deficits were observed for patients with carpal tunnel syndrome even though maximum pinch strength was similar. The path length, normalized by palm width of the thumb tip for the patients with carpal tunnel syndrome was less than for control participants (opposition: 2.2 palm width [95% CI, 1.8–2.6 palm width] versus 3.1 palm width [95% CI, 2.8–3.4 palm width], p < 0.001; circumduction: 2.2 palm width [95% CI, 1.9–2.5 palm width] versus 2.9 palm width [95% CI, 2.7–3.2 palm width], p < 0.001). Specifically, patients with carpal tunnel syndrome had a deficit of 0.3 palm width (95% CI, 0.04–0.52 palm width; p = 0.022) in the maximum position of their thumb tip ulnarly across the palm during opposition relative to control participants. The angular ROM also was reduced for the patients with carpal tunnel syndrome compared with the control participants in extension/flexion for the metacarpophalangeal (opposition: 34° versus 58°, p = .004; circumduction: 33° versus 58°, p < 0.001) and interphalangeal (opposition: 37° versus 62°, p = .028; circumduction: 41° versus 63°, p = .025) joints.

Conclusions

Carpal tunnel syndrome disrupts kinematics of the thumb during opposition and circumduction despite normal pinch strength.

Clinical Relevance

Improving understanding of thumb pathokinematics associated with carpal tunnel syndrome may help clarify hand function impairment associated with the syndrome given the critical role of the thumb in dexterous manipulation.     

Outcome of uncemented trapeziometacarpal prosthesis for treatment of thumb carpometacarpal joint arthritis

Background:

Osteoarthritis of the trapeziometacarpal joint of thumb occurs frequently and can be very disabling. Numerous surgical techniques including trapeziectomy with or without tendon interposition arthrodesis and partial or total joint arthroplasty with cemented and noncemented prosthesis have been described for the treatment of trapeziometacarpal joint osteoarthritis. Initial problems of osteolysis and implant loosening have been substantially reduced with improvement in implant design. The aim of this study is to demonstrate that trapeziometacarpal osteoarthritis of the thumb can be effectively treated with uncemented total joint replacement prosthesis.

Materials and Methods:

We retrospectively collected data for 16 trapeziometacarpal joint replacements in 14 patients. One patient was excluded as they required revision with trapeziectomy and ligament reconstruction following fracture of Trapezium. The trapeziometacarpal joint prosthesis was used in all cases and all operations were carried out by one surgeon. Clinical outcome was determined by a pre and postoperative patient rated wrist evaluation (PRWE) and Michigan Hand Questionnaire Score. Range of motion, grip, tip pinch and key pinch strength were measured and compared with the unoperated hand. Radiological assessment was carried out by plain radiographs for preoperative staging of arthritis and postoperative radiographs at latest followup for evaluation of osteolysis and implant loosening. Average followup period was 26 months.

Results:

There was an improvement in hand function and pain level based on PRWE and Mischigan Hand outcome Questionnaire Score. One patient had intraoperative fracture of Trapezium and subsequent radiographs at 14 months followup showed loosening of the trapezial component due to nonunion of the fracture and complete disintegration of the trapezium. There were no cases of dislocation or implant loosening for the remaining 15 CMC joints at the latest followup.

Conclusion:

The use of uncemented prosthesis in treatment of Questionnaire Score. Range of motion joint osteoarthritis gives excellent short term results in improving hand function in terms of strength and stability and achieving pain relief.     

Patellaposition und Patellofemoralarthrose nach unikompartimentellem Kniegelenkersatz

Background

Changes of patellar position (height, tilt, and shift) and arthritis of the patellofemoral joint might potentially influence outcome after unicompartmental knee replacement.

Objectives

The purpose of this work is to evaluate the influence of the aforementioned parameters on postoperative outcome.

Methods

Literature analysis via PubMed.

Results

A total of 12 relevant studies (three about Patellar height, two about patellar tilt and shift, seven about patellofemoral osteoarthritis) could be identified. Regarding Patellar height, two out of three studies demonstrated a postoperative decrease. With regard to patellar tilt and shift, only one study identified postoperative lateralization of the patella to be a predictor for poor outcome. The radiological appearance of arthritis of the patellofemoral joint does not significantly influence postoperative knee function except for cases where only the lateral patellar facet is affected. Anterior knee pain has no influence on clinical outcome.

Conclusion

Literature data do not allow for a precise statement about the possible influence of patellar position on the outcome after unicompartmental knee replacement. With proper patient selection, good results can be achieved despite patellofemoral osteoarthritis.