Lunate-capitate arthrodesis for scaphoid nonunion: a comparative study.

BACKGROUND: Scaphoid nonunion advanced collapse (SNAC) injuries are frequently associated with irreversible degenerative wrist arthritic changes that necessitate surgical intervention. Midcarpal fusion remains the mainstay of the management of SNAC II and III injuries. A successful four-corner fusion (4CF) relies on a stable lunate-capitate fusion (LCF). There have been reports of management relying solely on LCF. The outcomes of LC- and 4 C-fusions in SNAC injuries were not widely documented. The objective of this research is to provide valuable insights into the effectiveness of both fusion procedures in the management of SNAC II and III wrist injuries, with a focus on reporting associated complications, functional and radiological outcomes. PATIENTS AND METHODS: This retrospective study encompassed 65 patients diagnosed with SNAC II and III wrist injuries who underwent limited wrist fusion procedures between 2015 and 2024, with a minimum of 2 years of postoperative follow-up. Exclusion criteria encompassed patients with carpal instability, prior wrist surgical interventions, and scapholunate advanced collapse. Following the fusion procedure performed, patients were stratified into two groups: the LCF group consisting of 31 patients, and the 4CF group comprising 34 patients. Preoperative and intraoperative data were retrieved from the patient's medical records. At their final follow-up appointments, patients underwent comprehensive radiographic and clinical evaluations. Clinical outcomes including hand grip strength, range of motion, the Disabilities of the Arm, Shoulder, and Hand Score, and the Mayo Modified Wrist Score, were compared between groups. Any associated complications were reported. RESULTS: The average healing time was 74.7 ± 15.6 and 72.2 ± 13.2 days for the LCF and 4CF groups, respectively. At the final visit, all patients showed functional improvement relative to their preoperative status, with comparable wrist range of motions observed in both groups. The functional wrist scores were slightly better in the LCF patients (P > 0.05). The average grip strength was significantly greater in the LCF group (P = 0.04), with mean strength values of 86.8% and 82.1% of the contralateral side, for the LCF and 4CF groups, respectively. CONCLUSION: The LCF is not less efficient than the 4CF in the treatment of SNAC II and III wrist injuries. Through a less time-consuming procedure, LCF can efficiently provide comparable results to 4CF. LEVEL OF EVIDENCE: level IV evidence.

Long-term outcomes after capitate fractures: a median 16-year follow-up.

INTRODUCTION: The long-term effects of a capitate fracture are unknown. The aim of this study was to assess both clinical and radiological long-term outcomes after a capitate fracture. MATERIALS AND METHODS: From a cohort of 526 consecutive patients with post traumatic radial sided wrist pain, 23 were identified diagnosed with a capitate fracture. 16 of these (11 males and 5 females) with a median age at injury of 17.5 years (range 11-27 years) were eligible for a follow-up after a median of 16 years (range 8 to 17 years). In this study patients were examined using conventional radiographs, computed tomography (CT) and magnetic resonance imaging (MRI) at the time of injury and with CT at the follow-up. At follow-up radiological signs of osteoarthritis were graded in four stages and clinical outcome was evaluated by measuring range of wrist motion and grip and pinch strength. The subjective outcome was assessed using DASH and PRWE questionnaires. RESULTS: Five patients had isolated capitate fractures and 11 had concomitant fractures, 10 of which had a simultaneous scaphoid fracture. 14 patients had been treated non-surgically in a cast and two patients were treated surgically. None of the fractures were visible on conventional radiographs at the time of injury. At follow-up all fractures had healed without signs of avascular necrosis. In one patient, CT examination revealed osteoarthritis between the capitate and lunate. This did not cause clinical symptoms. Functional impairments and pain scores were low: median DASH score 0, median PRWE 3 and median VAS pain score 0. We found no impairment in range of motion or grip and pinch strength. CONCLUSIONS: At a median of 16-year follow-up, patients with a capitate fracture report normal self-assessed hand function as well as good wrist motion and strength. The risk of development of posttraumatic arthritis in the joints around the capitate is low.

Scaphocapitate arthrodesis with lunate preservation for Kienböck's disease: prospective outcomes study.

PURPOSE: The study evaluated the efficacy of SC arthrodesis with lunate preservation for treating patients diagnosed with stage IIIB or IIIC Kienböck's disease, who also exhibit neutral ulnar variance. The study further aimed to explore potential variations in outcomes between patients diagnosed with stage IIIB and IIIC Kienböck's disease. METHODS: Thirty-two patients diagnosed with stage IIIB (n = 19) and stage IIIC (n = 13) Kienböck's disease underwent SC arthrodesis with distal radius bone grafting stabilised by Herbert compression screws. All participants underwent pre- and post-operative assessments including VAS score for pain, ROM, grip strength, MMWS, and the Quick DASH score. Additionally, RS angle, LHI ratio, and CHI ratio were assessed. RESULTS: For all patients, the mean operative time was 73 min, follow-up was 45.6 months, time to union was 14 weeks, and time to full return to work was 24 weeks. The rate of union at the arthrodesis site was 91% (29 out of 32 patients) whilst the incidence of postoperative degenerative arthritis was 36% (8 out of 32 patients). Regarding changes in the means of outcomes from pre- to post-operatively, the VAS score decreased from 8.2 to 1.3 and grip strength improved from 36 to 79%. The RS angle was corrected from 59° to 50°. Significant improvements were noted in the mean MMWS from 45 to 75 and QuickDASH score from 78 to 21. However, no significant changes were observed in ROM, LHI, and CHI. There were no significant differences between patients with stage IIIB and stage IIIC in terms of these parameters, except for differences observed in the RS angle, LHI, and CHI preoperatively and in LHI and CHI postoperatively. CONCLUSION: Evidence level: II. Our research demonstrates that SC arthrodesis is a valuable approach for reducing pain, improving grip strength, and enhancing overall function in individuals with advanced Kienböck's disease. Importantly, our results indicate no notable differences in outcomes between patients diagnosed with stage IIIB or IIIC Kienböck's disease.

Stress fracture of capitate bone-A case report of an unusual fracture.

INTRODUCTION: The capitate is the largest, most central bone and the first to ossify in the wrist. It has a well-protected anatomic location, making traumatic or stress fractures extremely rare in clinical practice. Isolated fractures of the capitate bone are very uncommon and often without displacement due to the great stability provided by the intracarpal ligaments. PURPOSE OF THE STUDY: This study aimed to report a case of isolated stress fracture of the capitate related to the work activity of a mechanic. CASE REPORT: We report the case of a 23-year-old patient complaining of pain and swelling in the left wrist for 2 months without improvement after using analgesics. On physical examination, he presented pain on palpation in the central region of the wrist, pain when performing flexion and extension movements of the wrist, and frustrated edema. Magnetic resonance imaging diagnosed a stress fracture of the capitate bone. Conservative treatment with forearm-palmar immobilization for 2 months, analgesic medication, and physical therapy rehabilitation after immobilization were performed. After the complete resolution of the symptoms, the patient started to work in a new role. DISCUSSION: There are five case reports of stress fractures in the capitate-two in teenagers and three in adults, but none of them was a mechanic. Clinical suspicion can be formulated when repetitive activity is associated with the wrist in extension and specific location of pain and swelling. Individuals with an immature skeleton are more susceptible. The development of occupational disease should be considered in similar cases of insidious and persistent pain in the palm of people with high work demands. CONCLUSION: Stress fractures of the capitate bone are a disease that must be suspected in insidious and persistent pain in the palm of the hand. Magnetic resonance imaging is the best image test to diagnose this disorder, and conservative treatment is indicated.

Lateral Femoral Trochlea Flap Reconstruction of the Proximal Capitate: An Assessment of Congruity and Description of Technique.

PURPOSE: We examined morphologic similarities of the medial lateral femoral trochlea (MFT) and lateral femoral trochlea (LFT) osteochondral flaps for reconstruction of the proximal capitate. METHODS: Magnetic resonance imaging scans of the wrists and ipsilateral knees of 10 young healthy volunteers were obtained. Three morphologic parameters were investigated, comparing the MFT and LFT harvest sites to the capitate proximal pole. The correspondingly relevant surgical planes were compared. The coronal plane radius of curvature (ROC) of the capitate was compared with the sagittal planes of the MFT and LFT. The sagittal plane ROC of the capitate was compared to the axial planes of the MFT and LFT. The angular relationship between the dorsal cortical surface of the capitate and the proximal pole cartilage (proximal dorsal capitate pitch) was compared to the corresponding angles between the cortical bone and convex cartilage on the LFT and MFT. RESULTS: The average ratios of ROC for the coronal planes of the capitate to the MFT (0.61) and LFT (0.58) were similar. The average ratios of ROC for the sagittal planes of the capitate to the MFT (0.57) and LFT (0.86) were also similar. The proximal dorsal capitate pitch demonstrated greater similarity to the corresponding shape of the LFT (angular ratio, 1.01) than to that of the MFT (angular ratio, 0.74). CONCLUSIONS: The LFT and MFT demonstrate similar congruity to the proximal capitate in the sagittal and coronal planes of the wrist. The LFT dorsal pitch closely approximates the relationship of the proximal capitate pole to its dorsal cortical surface. CLINICAL RELEVANCE: In capitate fracture, fracture nonunion, or avascular necrosis, both the MFT and LFT demonstrate similarity to the proximal convex capitate morphology. The relationship between the cortical and chondral surfaces of the LFT is morphologically very similar to that of the proximal capitate.

Scapho-luno-capitate fusion with proximal lunate articular surface preservation for management of grade IIIA Kienböck's disease: a prospective case series.

BACKGROUND: Kienböck's disease is idiopathic lunate avascular necrosis, which may lead to lunate collapse, abnormal carpal motion and wrist arthritis. The current study aimed to assess the outcomes of treating stage IIIA Kienböck's disease by a novel technique of limited carpal fusion via partial lunate excision with preservation of the proximal lunate surface and scapho-luno-capitate (SLC) fusion. MATERIALS AND METHODS: We conducted a prospective study of patients with grade IIIA Kienböck's disease managed with a novel technique of limited carpal fusion comprising SLC fusion with preservation of the proximal lunate articular cartilage. Autologous iliac crest bone grafting and K-wires fixation were used to enhance the osteosynthesis of the SLC fusion. The minimum follow-up period was 1 year. A visual analog scale (VAS) and the Mayo Wrist Score were utilized for the evaluation of patient residual pain and functional assessment, respectively. A digital Smedley dynamometer was used to measure the grip strength. The modified carpal height ratio (MCHR) was used for monitoring carpal collapse. The radioscaphoid angle, scapholunate angle, and the modified carpal-ulnar distance ratio were used for the assessment of carpal bones alignment and ulnar translocation of carpal bones. RESULTS: This study included 20 patients with a mean age of 27.9 ± 5.5 years. At the last follow-up, the mean range of flexion/extension range of motion (% of normal side) improved from 52.8 ± 5.4% to 65.7 ± 11.1%, P = 0.002, the mean grip strength (% of normal side) improved from 54.6 ± 11.8% to 88.3 ± 12.4%, P = 0.001, the mean Mayo Wrist Score improved from 41.5 ± 8.2 to 81 ± 9.2, P = 0.002, and the mean VAS score reduced from 6.1 ± 1.6 to 0.6 ± 0.4, P = 0.004. The mean follow-up MCHR improved from 1.46 ± 0.11 to 1.59 ± 0.34, P = 0.112. The mean radioscaphoid angle improved from 63 ± 10º to 49 ± 6º, P = 0.011. The mean scapholunate angle increased from 32 ± 6º to 47 ± 8º, P = 0.004. The mean modified carpal-ulnar distance ratio was preserved and none of the patients developed ulnar translocation of the carpal bones. Radiological union was achieved in all patients. CONCLUSIONS: Scapho-luno-capitate fusion with partial lunate excision and preservation of the proximal lunate surface is a valuable option for treating stage IIIA Kienböck's disease, with satisfactory outcomes. Level of evidence Level IV. Trial registration Not applicable.

Cortical and trabecular bone structure of the hominoid capitate.

Morphological variation in the hominoid capitate has been linked to differences in habitual locomotor activity due to its importance in movement and load transfer at the midcarpal joint proximally and carpometacarpal joints distally. Although the shape of bones and their articulations are linked to joint mobility, the internal structure of bones has been shown experimentally to reflect, at least in part, the loading direction and magnitude experienced by the bone. To date, it is uncertain whether locomotor differences among hominoids are reflected in the bone microarchitecture of the capitate. Here, we apply a whole-bone methodology to quantify the cortical and trabecular architecture (separately and combined) of the capitate across bipedal (modern Homo sapiens), knuckle-walking (Pan paniscus, Pan troglodytes, Gorilla sp.), and suspensory (Pongo sp.) hominoids (n = 69). It is hypothesized that variation in bone microarchitecture will differentiate these locomotor groups, reflecting differences in habitual postures and presumed loading force and direction. Additionally, it is hypothesized that trabecular and cortical architecture in the proximal and distal regions, as a result of being part of mechanically divergent joints proximally and distally, will differ across these portions of the capitate. Results indicate that the capitate of knuckle-walking and suspensory hominoids is differentiated from bipedal Homo primarily by significantly thicker distal cortical bone. Knuckle-walking taxa are further differentiated from suspensory and bipedal taxa by more isotropic trabeculae in the proximal capitate. An allometric analysis indicates that size is not a significant determinate of bone variation across hominoids, although sexual dimorphism may influence some parameters within Gorilla. Results suggest that internal trabecular and cortical bone is subjected to different forces and functional adaptation responses across the capitate (and possibly other short bones). Additionally, while separating trabecular and cortical bone is normal protocol of current whole-bone methodologies, this study shows that when applied to carpals, removing or studying the cortical bone separately potentially obfuscates functionally relevant signals in bone structure.

Capitate shortening osteotomy with or without vascularized bone grafting for the treatment of early stages of Kienböck's disease.

PURPOSE: The study evaluates the procedures of capitate shortening osteotomy with or without vascularized bone grafting (VBG) for the treatment of stage II or IIIA Kienböck's disease with neutral ulnar variance. METHOD: Forty-five patients with stage II (n = 21) and IIIA (n = 24) Kienböck's disease were included in the study. Patients were classified into two groups; isolated capitate shortening (ICS) group included 21 patients (stage II [n = 10] and stage IIIA [n = 11]) treated by capitate shortening without VBG of the lunate. Combined capitate shortening (CCS) group includes 24 patients (stage II [n = 11] and stage IIIA [n = 13]) who treated by capitate shortening combined with VBG of the lunate from the dorsal distal radius based on the fourth + fifth extensor compartment artery. All patients were evaluated pre- and post-operative for pain as measured by visual analogue scale score (VAS), range of motion (ROM), grip strength, modified Mayo wrist score (MMWS), lunate height index (LHI) ratio, and carpal height index (CHI) ratio. RESULTS: The mean operative time for CCS procedure was 85 min (76 to 120) and for ICS was 58 min (47 to 65). The mean follow-up period for all patients was 33 months (29 to 47). Patients with stage IIIA Kienböck's disease treated by CCS procedure had better post-operative VAS, ROM, grip strength, MMWS, LHI, and CHI ratio than patients treated by ICS procedure. ICS procedure reported 28% failure rate versus 8% for CCS. No differences were found between CCS and ICS procedures in patients with stage II Kienböck's disease in the term of clinical, radiographic outcomes, or failure rate. CONCLUSION: Using CCS procedure for the treatment of stage IIIA Kienböck's disease (lunate height collapse) with neutral ulnar variance can restore height and dimensions of the collapsed lunate and subsequently improve the final outcomes with lower failure rate. However, in patients with stage II Kienböck's disease (maintained lunate height), no advantages were noticed for CCS over ICS procedure. Lunate height index might be considered a prognostic factor for the treatment outcomes of Kienböck's disease.

Trabecular architecture of the capitate and third metacarpal through ontogeny in chimpanzees (Pan troglodytes) and gorillas (Gorilla gorilla).

Chimpanzees (Pan troglodytes) and gorillas (Gorilla gorilla) both knuckle-walk in adulthood but are known to develop their locomotor strategies differently. Using dentally defined age-groups of both Pan and Gorilla and behavioral data from the literature, this study presents an internal trabecular bone approach to better understand the morphological ontogeny of knuckle-walking in these taxa. Capitate and third metacarpal bones were scanned by µCT at 23-43 µm resolution with scaled volumes of interest placed centrally within the head of the capitate and base of the third metacarpal. Trabecular measures related to activity level (size-adjusted bone volume/total volume, trabecular number, and bone surface area/bone volume) met expectations of decreasing through ontogeny in both taxa. Degree of anisotropy did not show statistical support for predicted species differences, but this may be due to the sample size as observed changes through ontogeny reflect expected trends in the capitate. Analyses of principal trabecular orientation corroborated known behavioral differences related to variation of hand use in these taxa, but only Pan showed directional patterning associated with suggested wrist posture. Assessment of allometry showed that the trabecular bone of larger animals is characterized by fewer and thinner trabeculae relative to bone size. In combination, these findings confirm the efficacy of trabecular bone in reflecting locomotor ontogeny differences between closely related taxa. These techniques show promise for use within the hominin fossil record, particularly for taxa hypothesized to be arboreal in some capacity.

Synovial Hemangioma of the Wrist With Cystic Invasion of Trapezoid and Capitate Bones.

Synovial hemangiomas (SHs) are rare lesions of the joints or tendon sheaths that are difficult to diagnose. We present the case of an 18-year-old man with an SH in the wrist joint. Physical examination revealed a slightly tender, ill-defined, nonpulsatile soft mass, 3 cm × 3 cm in size on the dorsal aspect of the left wrist. Computed tomography showed an irregular, ill-defined, soft tissue mass in the expanded joint space, which was formed by the scaphoid, trapezoid, and capitate bones. Magnetic resonance imaging showed the typical features of SH and also revealed cavitary erosion of the scaphoid, trapezoid, and capitate bones. An open arthrotomy was performed via a dorsal approach, and the mass was excised. The histological examination findings were consistent with the diagnosis of SH.

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.

Avascular Necrosis of the Carpal Bones Other Than Kienböck Disease.

Avascular necrosis (AVN) of the carpal bones other than Kienböck disease is a rare cause of chronic pain of the wrist. The scaphoid, capitate, and a smaller percent of lunates are at greater risk to develop AVN because of their peculiar intraosseous circulation; however, AVN has been reported in all the carpal bones. On the plain radiograph, AVN of the carpal bones may evolve through a normal radiograph, sclerosis, fragmentation, cyst formation, fracture, bone collapse, change of the carpal height, and alignment and progressive degenerative changes of the wrist joint. In the early stage of AVN, magnetic resonance imaging enhanced with gadolinium is a more sensitive and specific diagnostic tool than plain radiograph to demonstrate the bone marrow viability. Because of the rarity of case reports, the natural history of AVN of the carpal bones other than Kienböck disease is not well understood. The aims of different treatments are to prevent bone collapse, restore normal carpal height and alignment, and reduce the risk of progressive degenerative changes of the wrist joint.

Lunate fracture healing after partial capitate shortening in Kienböck disease.

BACKGROUND: It is unclear whether lunate fracture types in Kienböck disease correlate with the degree of fracture healing. This study aimed to review the clinical results of stage 3 Kienböck disease treated using partial capitate shortening (PCS) and to evaluate the healing rates of lunate fractures based on the fracture types. METHODS: Twenty-three patients were clinically and radiographically followed up for >2 years after PCS. The preoperative location and postoperative healing of the lunate fracture were evaluated using plain radiography, computed tomography, and/or magnetic resonance imaging. Results were evaluated using the Kienböck scoring system by Nakamura. RESULTS: PCS was clinically effective, demonstrating excellent and good results in 11 and 11 patients, respectively. Pain evaluated using the visual analog scale, wrist extension, flexion motion, and grip strength significantly improved postoperatively (p < 0.01). Fractures were preoperatively detected in all 23 cases. Fracture locations were preoperatively classified into five subtypes based on radiographs: volar pole in five patients, dorsal pole in three, coronal in five, transverse in nine, and ulnar in one. The overall union rate of the lunate fracture was 48%, whereas none of the coronal fractures healed. CONCLUSIONS: PCS was effective in treating stage 3 Kienböck disease. Coronal lunate fractures had a poor healing rate relative to those of the other fracture types. STUDY DESIGN: Clinical, retrospective study.

Three-Corner Arthrodesis (lunate - hamate - capitate) : clinical and kinematical evaluation.

In the absence of prosthetic arthroplasty offering good results for the treatment of wrist osteoarthritis, we studied the arthrodesis of three carpal bones (lunate - hamate - capitate) completed by triquetrum and scaphoid excision in the presence of Scapholunate Advanced Collapse (SLAC) or Scaphoid Nonunion Advanced Collapse (SNAC) stage II or III. Clinical data on eight patients between the ages of 32 and 61 years at an average of 29 months after surgery was analyzed. Seven patients reached fusion with a carpal height ratio of 0.39. These arc of dorsal-palmar flexion (DPF) attended 54° and the arc of radio-ulnar deviation (RUD) 29° using the optoelectronic stereophotogrammetry system. The mean polar radius (R) was 14.5° and the envelope shape coefficient (K) was 1.66. This operation could be considered as an alternative for the treatment of patients suffering of SNAC or SLAC stage II and III. Type of study/level of evidence : Therapeutic IV.

Treatment of Kienböck's Disease With Neutral Ulnar Variance by Distal Capitate Shortening and Arthrodesis to the Base of the Third Metacarpal Bone.

PURPOSE: We evaluated whether a surgical technique combining distal capitate shortening and arthrodesis to the base of the third metacarpal bone for the treatment of the early stages (stages II and IIIA) of Kienböck's disease with neutral ulnar variance resulted in pain relief, improvement in wrist motion, or changes in the radiographic evaluation. METHODS: This retrospective study reviewed 22 patients with early stages of Kienböck's disease with neutral ulnar variance, treated by distal capitate shortening and arthrodesis to the base of the third metacarpal bone. Patients were divided into 2 groups by disease stage: stage II (n = 12) and stage IIIA (n = 10). There were 8 women and 14 men, with an average age of 35.7 years. The following parameters were measured before and after surgery: visual analog scale (VAS) for pain evaluation, grip strength, range of motion (ROM), ulnar variance, carpal height index, lunate height index, and the scapholunate and scaphocapitate angles. The patients were evaluated in accordance with Modified Mayo Wrist Score (MMWS). RESULTS: The average follow-up period was 30.5 months (range, 26-36 months). The stage II group showed significant improvements in the mean VAS (58-5), ROM (57% to 73%), grip strength (54% to 75%), and MMWS (51-78). Patients in the stage IIIA group showed nonsignificant changes in mean VAS score (64-42.5), ROM (52.5% to 55.5%), grip strength (46.5% to 57.5%), and MMWS (36-50.5). Significant decreases in the carpal height index and scaphocapitate angle, and an increase in scapholunate angle in all stage IIIA patients were observed. CONCLUSIONS: Distal capitate shortening with capitometacarpal arthrodesis can alleviate pain and improve ROM and grip strength in patients with stage II Kienböck's disease, but not in those with stage IIIA. Moreover, it cannot prevent carpal collapse, especially in stage IIIA of the disease. We do not recommend this technique for treating stage IIIA patients. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

The Effect of Radioscapholunate Fusion With and Without Distal Scaphoid and Triquetrum Excision on Capitolunate Contact Pressures.

PURPOSE: To determine the effects of motion-increasing modifications to radioscapholunate (RSL) arthrodesis on capitolunate contact pressure in cadaveric wrist specimens. METHODS: Ten fresh-frozen cadaveric wrists were dissected of all superficial soft tissue, potted in polymethyl-methacrylate, and the carpus exposed via a ligament-sparing capsulotomy. An RSL arthrodesis was simulated using 2 2.4-mm distal radius plates with locking screws. The distal scaphoid pole and triquetrum were removed with an osteotome and rongeur, respectively. Contact area, pressure, and force were measured in the capitolunate joint during the application of a 35-N uniaxial load using pressure-sensitive film. Measurements were obtained before and after simulated RSL fusion, following distal scaphoidectomy and after triquetrectomy. RESULTS: The combination of RSL fusion with distal scaphoid excision (DSE) increased contact forces in the capitolunate joint by 50% over controls. An RSL fusion, and RSL fusion with DSE and triquetrum excision (TE), exhibited intermediate levels of contact force between controls and RSL fusion with DSE. Capitolunate contact pressures were similar between all experimental groups. Contact area in the capitolunate joint increased by 43% after RSL fusion with DSE over intact specimen controls. Lastly, contact area in wrists with RSL fusion, and RSL fusion with DSE and TE, were elevated, but not significantly different from intact controls. CONCLUSIONS: A DSE performed at the time of RSL fusion results in increased midcarpal joint contact force and area, with resultant contact pressures unchanged. Triquetrectomy, which has been previously shown to improve range of motion, did not increase contact forces in the capitolunate joint. CLINICAL RELEVANCE: If a surgeon is contemplating performing an RSL arthrodesis with DSE, we recommend adding a triquetrectomy to improve motion because this does not add to the potentially deleterious effects of increased midcarpal contact force.

The Capitate-to-Axis-of-Radius Distance (CARD): A New Radiographic Measurement for Wrist and Carpal Alignment in the Sagittal Plane.

PURPOSE: To determine the reliability of a new radiographic index evaluating sagittal radiocarpal alignment, the capitate-to-axis-of-radius distance (CARD). A secondary purpose was to validate this index by comparing values between normal wrists and those with distal radial fractures (DRFs) and rheumatoid arthritis (RA). METHODS: The CARD is defined as the perpendicular distance from the center of the capitate head to the axis of the radius. Inter- and intraobserver reliability was tested. Cronbach alpha was calculated, and 2 methods of measurement were compared. The superior one (volar border of radial shaft) was used in the second part of the study. The normal CARD was then compared with unilateral DRFs with dorsal displacement DRF (n = 25) and RA (n = 25). Correlations between the CARD and other radiographic parameters (dorsal angulation, radial inclination, and ulnar variance) were calculated as well as between the CARD and the severity of disease or fracture displacement (mild/moderate/severe). RESULTS: The CARD showed excellent intra- and interobserver reliability. The volar radius measurement method was superior to the midaxis method and was, therefore, used for the second portion of the study. The mean CARD for normal, fractured, and RA wrists was significantly different (2.2 ± 2.5 mm, 15.7 ± 6.5 mm and 0.2 ± 4.4 mm, respectively). There was a strong side-to-side correlation in normal wrists (r = 0.77) and a significant correlation between the CARD (mm) and the severity of deformity (RA, r = -0.7; DRF, r = 0.8). CONCLUSION: The CARD is a reproducible, easy-to-use measurement of sagittal carpal alignment with a strong side-to-side correlation. The CARD increases with dorsal angulation of the distal radius and decreases as severity of deformity with RA increases. CLINICAL RELEVANCE: The correlation of the CARD with severity of deformity in DRFs and RA makes it a useful method of assessing deformities in the sagittal plane. The normal wrist can be used as a comparison when evaluating the CARD in the setting of unilateral wrist disease.

Anatomical relationship of palmar carpal bone landmarks used in locating the lunate and capitate during palpation: A cadaveric investigation.

STUDY DESIGN: Descriptive in situ cadaveric study. INTRODUCTION: Performing accurately directed examination and treatment to the wrist requires clinicians to orient to carpal bone structures. PURPOSE OF THE STUDY: To examine the anatomical relationships that exist within the wrist-hand complex and identify the accuracy of surface anatomy mapping strategies for localizing anatomical landmarks using a palmar approach. METHODS: Twenty-three embalmed cadavers were dissected using standardized procedures. Metal markers were placed in the most prominent palmar landmark of key carpal structures. Relationships between the most prominent palpation landmarks and the carpal bones of interest were visualized using fluoroscopy. RESULTS: The most successful methods of palmar capitate localization included the midpoint of a line from trapezium tubercle to pisiform; the midpoint of a line from scaphoid tubercle to hamate hook; or the intersection (cross) of these 2 diagonal lines, with successful capitate identification 100% (23/23) of the time. The most successful method for locating the lunate included the midpoint of a line from the radial styloid process to the ulnar styloid process, which identified the lunate in 100% (23/23) of cases. DISCUSSION: The results of this cadaveric anatomical relationship study support the use of the midpoint of a line from pisiform to trapezium tubercle, the midpoint of a line from scaphoid tubercle to hamate hook, or a combination (cross) of these lines to locate the capitate from a palmar approach. In addition, the anatomical relationships examined in this study support the use of the midpoint of a line from the radial styloid process to ulnar styloid process to locate the lunate from a palmar approach. Knowledge of these anatomical relationships may improve the clinician's confidence in locating the capitate and lunate during intercarpal examination, special testing, and treatment. CONCLUSION: Results of this study provide information of the anatomical relationships of the carpal bones from a palmar approach, giving clinicians a foundation for proper orientation to the carpal bones during clinical examination and intervention. Further research is needed to evaluate the reliability and accuracy of these methods for surface palpation on live patients.

A simple method for bone age assessment: the capitohamate planimetry.

OBJECTIVES: To determine if the capitohamate (CH) planimetry could be a reliable indicator of bone age, and to compare it with Greulich-Pyle (GP) method. METHODS: This retrospective study included 391 children (age, 1-180 months). Two reviewers manually measured the areas of the capitate and hamate on plain radiographs. CH planimetry was defined as the measurement of the sum of areas of the capitate and hamate. Two reviewers independently applied the CH planimetry and GP methods in 109 children whose heights were at the 50th percentile of the growth chart. RESULTS: There was a strong positive correlation between chronological age and CH planimetry measurement (right, r = 0.9702; left, r = 0.9709). There was no significant difference in accuracy between CH planimetry (84.39-84.46 %) and the GP method (85.15-87.66 %) (p ≥ 0.0867). The interobserver reproducibility of CH planimetry (precision, 4.42 %; 95 % limits of agreement [LOA], -10.5 to 13.4 months) was greater than that of the GP method (precision, 8.45 %; LOA, -29.5 to 21.1 months). CONCLUSIONS: CH planimetry may be a reliable method for bone age assessment. KEY POINTS: • Bone age assessment is important in the work-up of paediatric endocrine disorders. • Radiography of the left hand is widely used to estimate bone age. • Capitatohamate planimetry is a reliable and reproducible method for assessing bone age.

Trigger wrist caused by avascular necrosis of the capitate: a case report.

BACKGROUND: Trigger wrist is a rare condition first described by Marti in 1960, and various causes have been reported. The condition mostly occurs with finger flexion and extension, and rarely with flexion and extension of the wrist itself. Avascular necrosis of the capitate is also a rare condition, first described by Jönsson in 1942. While some reports of this condition have been published, little is known about its etiology. Therefore, no established treatment exists. We report a case of trigger wrist caused by avascular necrosis of the capitate. CASE PRESENTATION: A 16-year-old right-handed male who was a high school handball player was referred to our department from a nearby hospital 5 months after the onset of pain in the dorsal aspect of the right wrist, with an unknown cause. At the previous hospital, imaging findings led to a diagnosis of avascular necrosis of the capitate, and conservative treatment with a wrist brace did not improve the pain. At the initial visit to our department, the patient was noted to have a painful trigger wrist that was brought on by wrist flexion and extension. Preoperative imaging findings led to a diagnosis of trigger wrist caused by capitolunate instability secondary to avascular necrosis of the capitate. We performed a partial excision of the proximal capitate with tendon ball interposition. Two years after surgery, the patient's clinical outcome was favorable, with no recurrence of wrist pain or triggering. CONCLUSIONS: Both trigger wrist and avascular necrosis of the capitate are rare disorders. When a patient presents with painful triggering at the wrist, surgeons must bear in mind that avascular necrosis of the capitate may result in this phenomenon. We recommend partial excision of the proximal capitate with tendon ball interposition for the treatment of this lesion.