Arthrodesis of distal interphalangeal and thumb interphalangeal joint: a retrospective cohort study of 149 cases.

BACKGROUND: Arthrodesis of finger joints is often the last line of treatment of severe pain due to osteoarthritis, rheumatoid arthritis, or mallet finger. At the Department of Orthopedic and Hand Surgery, Örebro University Hospital (ÖUH) in Sweden, the Kirschner-wire technique was standard until 2020, when the headless compression screw technique was introduced as a complement. There is no consensus on which method is superior. The purpose of this study was to examine the outcomes and complications associated with distal interphalangeal (DIP) joint and thumb interphalangeal (IP) joint arthrodesis, and to see whether these correlated with patient-dependent and treatment-related factors. METHODS: In a retrospective cohort study, we evaluated a total of 149 consecutive arthrodeses (118 DIP joint and 31 thumb IP joint) performed between 2012 and 2022. The primary outcome was risk factors for complications after arthrodesis. RESULTS: Osteoarthritis was the most common indication (56%) for arthrodesis. The majority of the patients were females (74%), and the median age was 62 (range 18-86). The complication frequency was 35%, with infection being the most common (25%). Time to completed follow up was < 12 weeks in the majority of the cases (58%). There were no significant differences in complication rate between the 136 joints operated using Kirschner wire and the 13 joints operated using headless compression screws. There was no significant increased risk of complications among smokers or patients with rheumatoid arthritis. Diabetes and surgeon experience had a significant influence on the risk of complication (p = 0.036 and p = 0.006, respectively). CONCLUSIONS: Osteoarthritis was the most common indication for arthrodesis and postoperative complications occurred at a rate similar to that reported in the existing literature. Diabetes and surgeon experience were identified as factors increasing the risk of postoperative complications in these DIP/thumb IP joint arthrodeses. However, there was no significant difference between the two techniques (Kirschner wire and headless compression screws) regarding complications. Further studies are needed in order to determine the optimal type of operation and choice of implant. TRIAL REGISTRATION: Researchweb CRIS #280,998, 26th of July 2023.

Quick and safe: why a k-wire-extension-block-fixation of a bony mallet finger is the favoured treatment.

INTRODUCTION: Mallet fingers are the most common tendon injuries of the hand. Bony avulsion distal finger extensor tendon ruptures causing a mallet finger require special attention and management. In this monocentral study, we analyzed the clinical and individual outcomes succeeding minimal invasive k-wire extension block treatment of bony mallet fingers. MATERIALS AND METHODS: In a retrospective study, we sent a self-designed template and a QUICK-DASH score questionnaire to all patients, who were treated because of a bony mallet finger between 2009 and 2022 and fulfilled the inclusion criteria. A total of 244 requests were sent out. 72 (29.5%) patients participated in the study. Forty-five men and twenty-seven women were included. RESULTS: 98.7% (n = 75) of the cases were successfully treated. Patients were highly satisfied with the treatment (median 8.0; SD ± 2.9; range 1.0-10.0). Based on the QUICK-DASH score, all patients showed no difficulties in daily life. The extent of avulsion did not influence the outcome. CONCLUSION: We conclude that the minimally invasive treatment of a bony mallet finger should be offered to every patient, because it is safe, fast, and reliable. Thus, we propose to perform extension-block pinning independently of the articular area.

Coverage of Palmar Mini Plates with Flexor Pulleys in the Treatment of Dorsal Fracture-Subluxation of the Proximal Interphalangeal Joint.

Introduction: Dorsal fracture dislocations (DFD) of the proximal interphalangeal joint (PIPJ) are challenging fractures. A palmar surgical approach and plate fixation has a high complication rate, including flexor contractions, reduction of range of motion (ROM) and secondary need for plate removal. Methods: We use the flexor tendon pulleys to cover the mini plate with the assumption that it may reduce the adhesion between the mini plates and the tendons and reduce postoperative complications. We present the outcomes of using this technique in eight patients. Results: All patients had an excellent outcome at a mean follow-up of 17 months, and none required removal of the implants. Conclusions: This study presents a surgical technique that may potentially reduce the high complication rate found after ORIF for treatment of DFD of the PIPJ. Therefore, improving the clinical outcomes after this type of surgery. Level of Evidence: Level IV (Therapeutic).

Arthrodesis of the interphalangeal joints of the hand by two-dimensional intraosseous wiring.

BACKGROUND: Numerous techniques for arthrodesis have been described to fix interphalangeal (IP) joints, and the fixation method should be considered on a case-by-case basis. This study aimed to investigate the availability of IP joint arthrodesis of the hand, using a two-dimensional intraosseous wiring (two-DIOW) method. METHODS: A total of 43 joints (19 thumb IP joints, 9 proximal finger interphalangeal (PIP) joints and 15 distal interphalangeal (DIP) joints in 29 patients with a mean age of 66 years (range, 24-85 y) were retrospectively analyzed. All operations were performed with two-DIOW method. We evaluated the bone union rate, correction loss, presence of any surgical complications, and oral steroid use in cases of joint fixation using the two-DIOW method. RESULTS: Of these 43 digits, 42 achieved bone union (97.7%). Non-union was seen in a thumb IP joint of mutilans rheumatoid arthritis. Mean correction loss of deviation was 1.0°, and flexion or extension angulation was 1.6° in the direction of extension. Surgical complications included mild nail deformity in 2 digits and wire irritation necessitating wire removal in 2 digits. Oral steroids were used for 18 of the 43 digits, including 2 digits complicated by nail deformities. There was no infection and skin necrosis in all digits with or without steroid use. CONCLUSIONS: The two-DIOW method appears to offer an effective method of IP joint fixation, but caution should be exercised in digits of severe joint destruction and in the treatment of wire knot.

Palmar Shift of the Proximal Interphalangeal Joint in Different Grip Positions as a Potential Risk Factor for Periphyseal Injuries in Adolescent Climbers.

INTRODUCTION: The aim of this study was to evaluate different grip positions as a contributing factor for primary periphyseal stress injuries of the finger phalanges in climbing. METHODS: Ultrasound imaging of the proximal interphalangeal joint was performed on 37 asymptomatic adolescent climbers. Longitudinal images were obtained of middle and ring fingers of both hands in different grip positions (open, half-open, and crimp), unloaded and loaded. The translation between the dorsal head of the proximal phalanx and the shaft of the middle phalanx was measured in an unloaded and loaded situation for all grip positions. The resulting difference was determined as the palmar shift. RESULTS: The mean age of the study population was 13 y. Results showed a palmar shift of 0.57 mm in a loaded crimp grip position compared to 0.13 mm in an open position and 0.20 mm in a half-open grip position. With a P value of <0.001, this shift was significantly higher in a crimp grip position compared to open or half-open grip positions. CONCLUSIONS: This leads to an increase in joint incongruity and much higher peak forces on the dorsal aspect of the epiphyseal-physeal-metaphyseal complex, which is particularly vulnerable during the adolescent growth spurt. Thus, climbing and training behavior should be adapted accordingly during this phase by avoiding the crimp grip position until epiphyseal fusion.

Patterns of Involvement of the Hand Joints in Classical Rheumatoid Arthritis.

BACKGROUND: Symmetrical involvement of the hand joints is described as characteristic of rheumatoid arthritis (RA). Quantitative data on specific patterns of involvement are lacking. OBJECTIVE: The Brigham Rheumatoid Arthritis Sequential Study was created for observational studies of patients with RA and afforded a unique opportunity to answer these questions. METHODS: Of 1598 subjects in the Brigham Rheumatoid Arthritis Sequential Study cohort, 535 met the following criteria: (1) disease duration of 7 years or greater, (2) seropositive, and (3) hand radiographs available. Patterns in specific hand joints based on physical examination and radiographic findings obtained at entry were identified. The level of symmetry of involvement of the metacarpophalangeal (MCP) and wrist joints was determined, as was the correlation between findings on physical examination and radiographic changes in the hand joints. RESULTS: The prevalence of joint space narrowing and/or erosions in each proximal interphalangeal (PIP) joints ranged between 11% and 18%. Joint space narrowing and/or erosions in the MCPs increased radially from the fifth to the second finger. Swelling and tenderness on physical examination of both the PIPs and MCPs also increased radially although the positive predictive value of physical examination as an indicator of joint damage decreased radially. The wrist was the most common joint involved both by physical examination (67%) and radiographically (70%). The right side was more involved radiographically. Analysis of radiographic changes in individual patients revealed that symmetrical findings in the wrists and MCPs occurred in only 67% of patients. CONCLUSIONS: The study describes the pattern of involvement of the hand joints in patients with long standing RA. Findings of interest include symmetrical involvement in only 67% of patients and a discordancy between physical findings and radiographic changes most marked in the more radial PIP joints.

Proximal Interphalangeal Joint Arthrodesis of the Hand Utilising a Rigid Intramedullary Device.

The proximal interphalangeal joint (PIPJ) is critical for proper finger and hand function. Arthritis of this joint can lead to significant pain and functional impairment. The APEX IP® Extremity Medical fusion device (Extremity Medical, Parsippany, New Jersey, USA) is an interlocking intramedullary screw device that provides a reliable method of hand PIPJ arthrodesis with good patient outcomes. We describe an easily reproducible surgical technique guide for using this device. Level of Evidence: Level V (Therapeutic).

Optical spectral transmission to assess glucocorticoid therapy response in patients with arthritis: a longitudinal follow-up comparison with joint ultrasound.

BACKGROUND: Optical spectral transmission (OST) is a modern diagnostic modality, able to assess the blood-specific absorption of light transmitted through a tissue, promising quantification of inflammation in the finger and wrist joints of patients with arthritis. To date, there are no adequate data regarding the diagnostic value of OST in the evaluation of inflammatory activity changes, during arthritis follow-up. Objectives of this study were therefore to examine the performance of OST in assessing response to anti-inflammatory therapy in patients with active arthritis and to explore OST associations with clinical, laboratory, and ultrasonographic (US) activity markers. METHODS: 1173 joints of 54 patients with arthritides of the wrist and finger joints were examined by OST before and after oral administration of glucocorticoids (GC), during a disease flare. For the same time-points patients underwent clinical, laboratory, and joint US [grayscale (GSUS), power-Doppler (PDUS)] examinations. The distribution of ΔOST-values between the two time-points was compared with the respective distributions of ΔPDUS and ΔGSUS by Bayesian statistical analyses. Moreover, the diagnostic performance of OST compared to a control group (2508 joints of 114 subjects) was examined by receiver operating characteristics and associations of OST values with clinical, laboratory, and arthrosonographic parameters were evaluated by correlation analyses. RESULTS: OST and US performed similarly in the assessment of inflammatory changes caused by GC (same value-change tendency in 83.2% of the cases). Bayesian statistics revealed no significant differences between ΔOST and ΔPDUS for all 3 examined joint categories (accuracy: metacarpophalangeal (MCP): 68.1%; proximal interphalangeal (PIP): 60.4%; wrists: 50.4%) and between ΔOST and ΔGSUS for MCP and PIP joints (accuracy: 51.1% and 78.7%, respectively). OST diagnostic performance (patients vs. controls) was excellent in both time-points [area under the curve (AUC) before GC=0.883(95%CI=0.83-0.94) and after GC=0.811(95%CI=0.74-0.881); p<0.001]. Furthermore, OST correlated significantly with all examined sonographic activity scores (all; p<0.001) and with swollen joint counts (p<0.01). CONCLUSIONS: OST was able to assess response to therapy in a similar way to joint US and correlated significantly with arthritis activity markers. Therefore, OST has proved to be a valuable tool to assist disease activity monitoring in the examined cohort. TRIAL REGISTRATION: German Registry of Clinical Trials, DRKS00016752.

Open Reduction and Internal Fixation of Dorsal Fracture-Dislocation of the Proximal Interphalangeal Joint Using a Plate: A Series of 37 Patients.

Background: Open reduction and internal fixation with a plate is one of the alternative treatments for fracture-dislocation of the proximal interphalangeal (PIP) joint. However, it does not always lead to satisfactory results. The aim of this cohort study is to describe the surgical procedure and discuss the factors affecting the treatment results. Methods: We retrospectively reviewed 37 cases of consecutive unstable dorsal fracture-dislocation of the PIP joint treated using a mini-plate. The volar fragments were sandwiched with a plate and dorsal cortex, and screws were used as subchondral support. The average rate of articular involvement was 55.5%. Five patients had concomitant injuries. The mean age of the patients was 40.6 years. Mean time between injury and operation was 11.1 days. The average postoperative follow-up duration was 11 months. Active ranges of motion, % total active motion (TAM) were evaluated postoperatively. The patients were divided into two groups according from Strickland score and Gaine score. Fisher's exact test, Mann-Whitney U test and a logistic regression analysis were used to evaluate the factors affecting the results. Results: The average active flexion, flexion contracture at the PIP joint, and % TAM were 86.3°, 10.5° and 80.6%, respectively. Group I included 24 patients who had both excellent and good scores. Group II included 13 patients who had neither excellent nor good scores. When the groups were compared, there was no significant relationship between the type of fracture-dislocation and the extent of articular involvement. There were significant associations between outcomes and patient age, period from injury to surgical intervention and presence of concomitant injuries. Conclusions: We concluded that meticulous surgical technique leads to satisfactory results. However, factors, including the patient's age, time from injury to surgery and the presence of concomitant injuries needing adjacent joint immobilisation, contribute to unsatisfactory outcomes. Level of Evidence: Level IV (Therapeutic).

Arthritis or maybe not? Pachydermodactyly: the great mimicker of juvenile idiopathic arthritis.

Arthritis in the paediatric population is the hallmark of many rheumatic inflammatory diseases, as well as other cutaneous, infectious, or neoplastic conditions. It can be quite devastating, whereby prompt recognition and treatment of these disorders are essential. However, arthritis can sometimes be mistaken for other cutaneous or genetic conditions leading to misdiagnosis and overtreatment. Pachydermodactyly is a rare and benign form of digital fibromatosis, usually manifested by swelling of the proximal interphalangeal joints of both hands, mimicking arthritis. The authors report a case of a 12-year-old boy with a one-year history of painless swelling of the proximal interphalangeal joints of both hands that was referred to the Paediatric Rheumatology department due to the suspicion of juvenile idiopathic arthritis. The diagnostic work-up was unremarkable, and the patient remained asymptomatic over an 18-month follow-up period. A diagnosis of pachydermodactyly was assumed and no treatment was introduced, given the benign nature of the disorder and absence of symptoms. Therefore, it was possible to safely discharge the patient from the Paediatric Rheumatology clinic.

Dynamic study of the finger interphalangeal joint volar plate-motion analysis with magnetic resonance cinematography and histologic comparison.

OBJECTIVE: We aimed to further improve knowledge about volar plate (VP) motion of the finger proximal interphalangeal joint (PIP), by analyzing the dynamic VP shape during a full range of finger flexion using magnetic resonance cinematography of the fingers (MRCF), and to compare the results with anatomical cross sections from cadaver specimens. MATERIALS AND METHODS: The dynamic sagittal VP shape was visualized with MRCF in a total number of 23 healthy volunteers. The length, angle, and thickness as well as the contact length of the VP to the PIP joint base were measured. Statistical analysis included t-test or rank-sum testing. Anatomical cross sections with differing degrees of PIP joint flexion were obtained from 12 cadaver specimens (fingers) for comparison. RESULTS: Significant positive correlations between PIP joint flexion angle and VP area, length, depth and the VP contact length were found. This matched histologically to fiber rearrangements especially within the loose third VP layer. CONCLUSION: Our study analyzed the full range of motion dynamic VP shape of the PIP joint using MRCF. This contributes to a more precise understanding of the complex interaction of the VP with the PIP joint and may facilitate evaluation of clinical cases such as VP avulsion or pulley rupture.

Radiological positioning of a proximal interphalangeal joint resurfacing implant: Reliability and functional outcomes correlation.

OBJECTIVES: The aims of this study were to define radiological measurements for quantifying the position of a surface replacing implant (CapFlex-PIP) in the proximal interphalangeal (PIP) joint, to test the reliability of these measurements, and to explore whether implant position influences patient-reported and clinical outcomes one year after surgery. MATERIAL AND METHODS: We developed 7 radiographic measurements to quantify the position of the proximal and distal implant components. Two independent surgeons analyzed the 1-year postoperative radiographs of 63 fingers documented in our registry. Inter-rater reliability of these measurements was calculated with the intraclass correlation coefficient (ICC). Correlations between the radiographic measurements and PIP range of motion (ROM), the brief Michigan Hand Outcomes Questionnaire (MHQ), and pain were determined using Spearman's correlation coefficient. Radiographic measurements of patients with the worst and best postoperative ROM were compared using the Mann-Whitney-U test. RESULTS: Inter-rater reliability was only good for 1 measurement (ICC = 0.89), but poor to moderate for the other measurements (ICC ranging from 0.34 to 0.69). These measurements neither correlated with ROM, brief MHQ nor pain based on correlation coefficients ranging from 0.00 to 0.31. There were no relevant differences in the radiographic measurements between patients with the worst and best ROM. CONCLUSION: The position of the CapFlex-PIP implant could not be reliably quantified on plain radiographs. The lack of correlations between implant position and postoperative outcomes can be attributed either to the unreliable measurements or the actual lack of influence of the implant position on pain and function.

Arthroplasty of the Proximal Interphalangeal Joint With the TACTYS Prosthesis: Clinical and Radiographic Results With a Mean Follow-up of 5 Years.

BACKGROUND: Degenerative arthritis of the proximal interphalangeal (PIP) joint of the long fingers is a common disorder affecting mainly a female middle-aged population. Conservative treatment is often effective, but in some cases, pain can persist which can lead to invalidating function. Besides denervation and arthrodesis, arthroplasty is a valuable alternative treatment. The goal of this retrospective study was to determine the clinical and radiological outcomes of the TACTYS prosthesis with a mean follow-up of more than 5 years. METHODS: Between October 2005 and August 2019 10 joints in 9 patients, one patient had two prostheses in two separate fingers (4 males and 6 women) were treated for painful degenerative arthritis of the long fingers with a TACTYS prosthesis (Stryker Inc, Kalamazoo, Michigan). Power grip and pinch force were tested preoperatively and postoperatively, and the functional outcome survey is performed using the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH), recall QuickDASH, and Patient-Rated Wrist Evaluation standardized questionnaires scored of 100 and the Visual Analog Scale (VAS) from 0 to 10. RESULTS: Mean follow-up was 65.70 months (range: 23-106). Mean age was 71.5 years (range: 64-83). QuickDASH score evolved from 68.43 to 41.92, range of motion from 37.5° to 45.1°, VAS from 6.65 to 1/10. Power grip and precision pinch evolved from 16.44 to 20.80 kg and 1.97 to 2.85 kg, respectively. CONCLUSIONS: TACTYS arthroplasty can be proposed for people who have been treated long enough with unsuccessful conservative treatment. Infection rate is still the highest complication, which can evolve in invalidating arthrodesis. It should be proposed exceptionally if the PIP joint arthritis causes invalidating functional pain.

Proximal Interphalangeal Joint Congruity: A Biomechanical Study.

BACKGROUND: Surgical approaches to the proximal interphalangeal (PIP) joint often require disruption of soft tissue stabilizers. Additionally, PIP joint injuries frequently result in soft tissue disruption. This study evaluates the necessity of repairing soft tissue stabilizers by assessing their role in maintaining native joint congruity. METHODS: Eight specimens were used to evaluate congruity at 0° and 30° flexion when loaded with 2 N of valgus force. This was performed in the native joint and after sequential sectioning of the surrounding ligaments in order: volar plate (VP), radial collateral ligament (CL), and ulnar CL. The skin flap was sutured with the ligaments unrepaired and the load was reapplied. Radiographs were taken after each load and used to measure the joint line convergence angle (JLCA). RESULTS: Mean JLCA increased in both degrees of flexion after ligaments were sectioned but was only significantly different from the native joint after the VP was disrupted along with 1 CL. Joint congruity improved following repair of the skin flap in both degrees of flexion but was not significant. Joints were more congruent in 30° flexion for all subgroups, but none were significantly different compared to 0° flexion. CONCLUSIONS: Disruption of the VP is insufficient to significantly alter PIP joint congruity. While sectioning of both the VP and CLs resulted in a statistically significant change in joint congruity, mean JLCA demonstrated changes of minor clinical significance. The osseous anatomy of the phalanges imparts inherent stability that maintains a congruent joint despite loss of the soft tissue stabilizers.

Closed Reduction and Percutaneous Pinning for Treatment of Proximal Interphalangeal Joint Pilon Fractures.

BACKGROUND: Proximal interphalangeal (PIP) joint pilon fractures are among the challenging hand injuries, which are often associated with a wide range of complications. This study aimed to report the clinical and radiological outcomes of closed reduction and percutaneous Kirschner wire (KW) insertion with or without bone cement application (for the fabrication of an external fixator) in the treatment of PIP joint pilon fractures. METHODS: Twenty pilon fractures underwent closed reduction and percutaneous KW fixation through a modified technique. At the end of the follow-up period, 3 questionnaires-Quick Disabilities of the Arm, Shoulder, and Hand (Quick DASH), Visual Analogue Scale for pain, and Patient-Rated Wrist Evaluation-were completed. The radiological outcome was assessed by radiography. Range of motion, and grip and pinch strength were measured. RESULTS: The mean follow-up period was 14.57 ± 4.03 months (range, 12-20 months). The mean range of motion of PIP at the end of the follow-up period was 89.64° ± 10.82° (range, 65°-100°). The mean difference in the range of motion in the contralateral side was 21.4° ± 13°. The mean of the Quick DASH score was 13.50 ± 2.92 (range, 11-21). Two patients had residual articular malalignment, and 3 patients had angular or rotational malunion. CONCLUSION: By treating pilon fractures with the proposed technique, we achieved a satisfactory outcome. The acceptable articular and axial alignment was achieved in 75% of patients, and complications were low. The flexibility of percutaneous KW insertion and handmade external fixators makes these approaches convenient for treating PIP joint pilon fractures.

Prediction of radiographic progression during a treat-to-target strategy by the sequential application of MRI-proven bone marrow oedema and power-Doppler grade ≥2 articular synovitis in rheumatoid arthritis: Retrospective observational study.

OBJECTIVES: To investigate the appropriate timing, useful findings and combination of magnetic resonance imaging (MRI) and ultrasound (US) for predicting the radiographic progression in early rheumatoid arthritis (RA). METHODS: Forty-four active RA patients, who examined by both of MRI and US in the symptomatic wrist and finger joints, were recruited in Nagasaki University Hospital from 2010 to 2017 and treated by the treat-to-target therapeutic strategy for 1 year. MRI was evaluated by RA MRI scoring and US by Outcomes Measures in Rheumatology Clinical Trial, respectively. Plain radiographs were assessed by the Genant-modified Sharp score for the symptomatic side in the same manner as MRI and US. Radiographic progression was defined as an annual increase ≥0.75 at 1 year. Factors associated with radiographic progression were analysed. Also, the optimal combination of MRI and US at each timepoint was considered. RESULTS: Logistic regression model revealed that MRI-proven bone marrow oedema at baseline and 6 months and joint counts of power-Doppler grade ≥2 articular synovitis at 3 or 6 months were significantly associated with radiographic progression at 1 year. CONCLUSION: This study may suggest the favourable timing and combination of MRI and US at each point to predict radiographic progression in patients with early-stage RA.

Fully automatic software for detecting radiographic joint space narrowing progression in rheumatoid arthritis: phantom study and comparison with visual assessment.

PURPOSE: We have developed an in-house software equipped with partial image phase-only correlation (PIPOC) which can automatically quantify radiographic joint space narrowing (JSN) progression. The purpose of this study was to evaluate the software in phantom and clinical assessments. MATERIALS AND METHODS: In the phantom assessment, the software's performance on radiographic images was compared to the joint space width (JSW) difference using a micrometer as ground truth. A phantom simulating a finger joint was scanned underwater. In the clinical assessment, 15 RA patients were included. The software measured the radiological progression of the finger joints between baseline and the 52nd week. The cases were also evaluated with the Genant-modified Sharp score (GSS), a conventional visual scoring method. We also quantitatively assessed these joints' synovial vascularity (SV) on power Doppler ultrasonography (0, 8, 20 and 52 weeks). RESULTS: In the phantom assessment, the PIPOC software could detect changes in JSN with a smallest detectable difference of 0.044 mm at 0.1 mm intervals. In the clinical assessment, the JSW change of the joints with GSS progression detected by the software was significantly greater than those without GSS progression (p = 0.004). The JSW change of joints with positive SV at baseline was significantly higher than those with negative SV (p = 0.024). CONCLUSION: Our in-house software equipped with PIPOC can automatically and quantitatively detect slight radiographic changes of JSW in clinically inactive RA patients.

New body surface indexes for germinal matrix: DIP joint extension boundary line and dorsal distal interphalangeal crease.

BACKGROUND: Knowledge of the proximal edge of the germinal matrix is essential to avoid injuries in the germinal matrix. The previous index such as terminal tendon insertion is not visible from the body surface. The purpose of this study was to examine the relationship between the proximal edge of the germinal matrix and the body surface indexes by ultrasonographic measurements. METHODS: All participants underwent X-rays of the hand and were grouped based on the presence or absence of osteoarthritis in the distal interphalangeal (DIP) joint. The distance from the proximal edge of the germinal matrix to dorsal distal interphalangeal crease (parameter D1), and to ''DIP joint extension boundary line'' (parameter D2) were measured using ultrasonography. RESULTS: Thirty middle fingers of 24 patients were enrolled; 13 fingers were in control group and 17 fingers were in Heberden's node group. The average of parameter D1 was 6.17 mm (SD 1.12) in the control group (N = 13), and was 7.04 mm (SD 1.31) in Heberden's node group (N = 17) without significant difference. The DIP joint extension boundary line was not visible in 7 fingers with severe DIP joint osteoarthritis. The average of parameter D2 was 0.00 mm (SD 0.00) in the control group (N = 13), and was 0.04 mm (SD 0.13) in Heberden's node group (N = 10). CONCLUSIONS: We suggest that DIP joint extension boundary line and dorsal distal interphalangeal crease are valuable indexes to predict the proximal edge of the germinal matrix from the body surface. Though the DIP joint extension boundary line was not visible in some cases, once it has been sighted, the line shows where the germinal matrix exactly is.

3D planning and patient specific instrumentation for intraarticular corrective osteotomy of trapeziometacarpal-, metacarpal and finger joints.

BACKGROUND: Intra-articular malunions of the finger can lead to deformity and loss of function and can be treated with intra-articular corrective osteotomies. The aim of this study was to evaluate radiographic joint congruency, feasibility and functional outcome of three-dimensional (3D) printed patient-specific instrumentation (PSI) for corrective osteotomies at the trapeziometacarpal and finger joints. METHODS: Computer-tomography (CT) scans were acquired preoperatively for standard 3D planning, which was followed by calculation of cutting planes and the design of individualized bone surface contact drilling, sawing and reposition guides. Follow-up CT scans and clinical examinations (range of motion, grip strength) were performed. Postoperative complications were documented and patient-reported outcome measurements were assessed (Single Assessment Numeric Evaluation (SANE) score, brief Michigan Hand Questionnaire (MHQ)). RESULTS: Ten patients (mean age 28.4 ± 12.8,range 13.8-51.3) years) were included with a mean follow-up of 21 ± 18 (3-59) months including seven osteotomies at the trapeziometacarpal or metacarpophalangeal joints and three at the proximal interphalangeal joint (PIP). All radiographic follow-up examinations showed the planned correction with good joint congruency and regular osseous consolidation. At the latest follow-up, the range of motion (ROM) increased and the average grip strength recovered to the level of the contralateral side. No postoperative complication was detected. The mean SANE score improved from 44 ± 23 (0-70) to 82 ± 12 (60-90) after a mean of 72 ± 20 (44-114) months. The mean postoperative brief MHQ was 92 ± 8 (71-98). CONCLUSION: The use of 3D PSI in treating intra-articular malunions at the trapeziometacarpal and finger joints restored articular congruency accurately. ROM and grip strength improved postoperatively comparable to the healthy contralateral side and patient-reported outcome measures improved after medium-term follow-up.