Peter Axelsson

Ulnar Head Replacement: 21 Cases; Mean Follow-Up, 7.5 Years

PURPOSE To report clinical and radiographic outcomes for the Herbert ulnar head prosthesis after a mean of 7.5 years (range, 2.0-12.5 years). METHODS We performed 22 Herbert ulnar head prosthesis arthroplasties between 2000 and 2011. Five were primary procedures, and the remaining 17 were done after an average of 2 (range, 1-5) previous operations. The mean age at surgery was 55 years (range, 31-74 years). Follow-up including clinical examination, standardized questionnaires, and radiographic examination was done after mean 7.5 years (range, 2.0-12.5 years) in 21 cases. We used the Disabilities of the Arm, Shoulder, and Hand questionnaire, the Patient-Rated Wrist Evaluation questionnaire, and the Mayo wrist score questionnaire. Pain and satisfaction were evaluated with a 10-cm visual analog scale (VAS). Measurements of range of motion and strength for grip were recorded. RESULTS Wrist range of motion was not affected by the arthroplasty except for supination, which significantly improved from 55° to 70°. At follow-up, grip strength averaged 25 kg (range, 10-48 kg) in the operated wrists and 31 kg (range, 8-74 kg) on the contralateral side. Visual analog scale-pain averaged 2.9 (range, 0-8.7) during activity and 1.7 (range, 0-7) at rest. Satisfaction VAS was 8.9 (range, 4.3-10). Five patients had VAS-pain above 5 during activity, and 1 patient was dissatisfied and regretted having undergone arthroplasty. Mean outcomes were 27 (range, 5-50) for Disabilities of the Arm, Shoulder, and Hand measure, 31 (range, 0-90) for the Patient-Rated Wrist Evaluation score, and 71 (range, 30-90) for the Mayo wrist score. One patient was reoperated with capsuloplasty 9 months after the arthroplasty owing to recurrence of painful instability. Full stability was not achieved but the pain resolved. None of the implants showed any radiographic signs of loosening. CONCLUSIONS The Herbert ulnar head prosthesis was a safe method of treatment and provided satisfactory midterm results for selected cases of distal radioulnar joint disorders. CLINICAL RELEVANCE Increased knowledge of performance for ulnar head implant arthroplasty may aid surgical decision making for distal radioulnar joint disorders. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.

Patients with triangular fibrocartilage complex injuries and distal radioulnar joint instability have reduced rotational torque in the forearm

A total of 20 patients scheduled for wrist arthroscopy, all with clinical signs of rupture to the triangular fibrocartilage complex and distal radioulnar joint instability, were tested pre-operatively by an independent observer for strength of forearm rotation. During surgery, the intra-articular pathology was documented by photography and also subsequently individually analysed by another independent hand surgeon. Arthroscopy revealed a type 1-B injury to the triangular fibrocartilage complex in 18 of 20 patients. Inter-rater reliability between the operating surgeon and the independent reviewer showed absolute agreement in all but one patient (95%) in terms of the injury to the triangular fibrocartilage complex and its classification. The average pre-operative torque strength was 71% of the strength of the non-injured contralateral side in pronation and supination. Distal radioulnar joint instability with an arthroscopically verified injury to the triangular fibrocartilage complex is associated with a significant loss of both pronation and supination torque. Level of evidence: Case series, Level IV.

The microsurgical training programme in Gothenburg, Sweden: early experiences

Abstract Objective: Microsurgical techniques are increasingly used in routine surgical practice as well as in biomedical research. The training opportunities at standardised training courses are limited, and no microsurgical training facility or programme existed in Scandinavia before 2013. Methods: A microsurgery laboratory was set up and two different courses were started, aiming separately at biomedical researchers and surgeons. The course for biomedical researchers teaches basic microsurgical skills such as vessel isolation, cannulation, and arterial microvascular suture under magnification. The more advanced course for surgeons focuses on various techniques of microvascular and nerve anastomosis. Both courses use a combination of theory and practice, with emphasis on the practical part, the course for surgeons also includes clinically relevant information. Results: Twelve 5-day courses using both non-living models and exercises on laboratory animals have been conducted and attended by 49 researchers and 44 surgeons. The organisation and the programme of the training courses as well as ‘The 4E concept’ behind the course (educational curriculum, equipment, ergonomy, and evaluation) are further detailed. Conclusions: We have successfully established the first training laboratory and series of microsurgical training courses in Scandinavia at two different levels. The experience from the first 12 courses shows the need for this type of structured training, and confirms that the microsurgical education curriculums needs to be adapted to participants’ prerequisites and expectations, and various difficulty levels should be considered.

Forearm Torque and Lifting Strength: Normative Data

PURPOSE To establish reference values for new methods designed to quantitatively measure forearm torque and lifting strength and to compare these values with grip strength. METHODS A total of 499 volunteers, 262 males and 237 females, aged 15 to 85 (mean, 44) years, were tested for lifting strength and forearm torque with the Kern and Baseline dynamometers. These individuals were also tested for grip strength with a Jamar dynamometer. Standardized procedures were used and information about sex, height, weight, hand dominance, and whether their work involved high or low manual strain was collected. RESULTS Men had approximately 70% higher forearm torque and lifting strength compared with females. Male subjects aged 26 to 35 years and female subjects aged 36 to 45 years showed highest strength values. In patients with dominant right side, 61% to 78% had a higher or equal strength on this side in the different tests performed. In patients with dominant left side, the corresponding proportions varied between 41% and 65%. There was a high correlation between grip strength and forearm torque and lifting strength. Sex, body height, body weight, and age showed a significant correlation to the strength measurements. In a multiple regression model sex, age (entered as linear and squared) could explain 51% to 63% of the total variances of forearm torque strength and 30% to 36% of lifting strength. CONCLUSIONS Reference values for lifting strength and forearm torque to be used in clinical practice were acquired. Grip strength has a high correlation to forearm torque and lifting strength. Sex, age, and height can be used to predict forearm torque and lifting strength. Prediction equations using these variables were generated. CLINICAL RELEVANCE Normative data of forearm torque and lifting strength might improve the quality of assessment of wrist and forearm disorders as well as their treatments.

New Methods to Assess Forearm Torque and Lifting Strength: Reliability and Validity

PURPOSE To determine the repeatability and validity of new methods designed to objectively measure forearm torque and lifting strength in a clinical setting. METHODS Twenty-eight healthy volunteers, 19 women and 9 men, were tested for lifting strength and forearm torque with the Kern and Baseline dynamometers. Two raters tested each participant on 3 occasions in the standing position. One of the raters also examined 15 subjects, 3 times, for forearm torque in the seated position and for lifting strength and forearm torque by the Work Simulator II, Baltimore Therapeutic Equipment (BTE II). Intraclass correlation coefficients (ICC) model 2,1 was used to calculate ICCs for intra- and interrater reliability. The same ICC model and Bland-Altman plots were used to analyze the validity and agreement between the new test methods and the BTE II equipment and for comparison between tests performed in the standing and seated positions. RESULTS Intra- and interrater reliability for forearm torque measurements with both the Baseline and the BTE II demonstrated ICCs between 0.88 and 0.96. The comparison between the Baseline and the BTE equipment yielded lower ICCs of 0.74 to 0.88 but they were still substantial and in good agreement. The ICCs for torques recorded in the standing and seated position were 0.89 to 0.96. Lifting strength, measured in 3 different positions of forearm rotation, yielded ICC values between 0.84 and 0.96 for both raters and with both the Kern and the BTE II instruments. Similarly, comparisons between the Kern and the BTE II methods showed ICC values between 0.91 and 0.95. CONCLUSIONS Both the Baseline and the Kern dynamometers demonstrated excellent intra- and interrater repeatability. Except for forearm torque test in direction of pronation, which had a slightly lower ICC of 0.74, our new methods were valid when the BTE II was used as the reference standard. Assessments in the standing or seated position for torque measurements made little difference. Thus, we found the quality of measurements performed with our new methods sufficient for future studies of forearm torque and lifting strength. CLINICAL RELEVANCE Simple, yet reliable, methods to quantify torque and lifting strength in a clinical setting have the potential to improve evaluations of wrist and forearm disorders as well as their treatments.

Three-Dimensional Virtual Planning for Corrective Osteotomies Made a Difference

Objective: There is increased clinical use of 3-dimensional (3D) virtual planning and 3D printed patient-specific guides to correct malunited fractures. Previous studies have investigated the accuracy and possible improvements in outcome for this technology. The focus has foremost been on the benefits of the 3D printed guides while little research is done on the impact of the preceding 3D virtual planning. The authors’ experience is that digital manipulation of detailed 3D images uncovers information that can influence the preoperative plan. The main purpose of this study was to examine if the 3D virtual planning process had affected the final choice for treatment. Materials and Methods: This retrospective study reviews a consecutive series of 23 cases of corrected malunited radius fractures, treated between 2011 and 2015. Bilateral, high-resolution forearm computed tomographic (CT) scans were acquired from each patient. With use of Materialise Mimics software, 3D models that could be digitally manipulated were created. For all but 1 patient, the healthy forearm was mirrored and used as a template for correction. Three-dimensional virtual planning took place during web meetings between the surgeon and the clinical engineer. Different osteotomy locations and angles and different fragment positions and osteosynthesis plates were digitally evaluated. This allowed the surgeon to choose his preferred treatment plan based on the virtual plate fit, fragment position, bone contact surface, natural ulnar variance seen on the contralateral side, and evaluation of the distal radioulnar joint congruency after virtual reduction. Our review consisted of comparing the preliminary preoperative surgical plans before interaction with the surgeon and the clinical engineer, derived from 2D planning with either standard radiographs or CT images, with the final chosen 3D surgical plan after interaction. The 3D virtual planning was considered to be different from the preliminary 2D planning when it demonstrated the need for at least 1 of the following: (A) plate contouring, (B) bone removal for improved plate fit, (C) change in osteotomy levels or directions, (D) double level osteotomy, (E) change in ulnar variance from neutral, (F) over- or undercorrection compared with the parameters of the contralateral side, (G) not using the contralateral side as a template for correction, (H) avoiding corrective osteotomy. Results: The preliminary 2D surgical plan before interaction between surgeon and clinical engineer was changed for 14 of the 23 patients. Category A counted 2 cases, B 2 cases, C 4 cases, D 1 case, E 4 cases, F 1 case, G 1 case, and H 2 cases. For the remaining 9 cases, the preliminary preoperative plan was chosen as final procedure. Conclusion: Limitations of this study include the retrospective design. As a consequence, details of the preoperative radiological planning were not comprehensively defined. Even so, this study showed that additional or new information acquired by the virtual planning led to a change of surgical procedure in 60% of the cases. Selection of a more ideal surgical method has the potential to improve outcomes of corrective osteotomies.

Reliability of New Methods to Quantify Forearm Torque and Lifting Strength

Objective/Hypothesis: Forceful forearm rotation and lifting strength are important aspects of upper extremity function. Yet they are rarely assessed in relation to wrist and forearm pathologies, or their treatments. Absence of reliable methods that are easy to use might be one reason for this discrepancy. We designed 2 new procedures to quantify forearm torque and lifting strength in a clinical setting. The objective of this study was to determine the intra- and interrater reliability of these methods. Materials and Methods: We used 2 commercially available dynamometers, the digital Baseline wrist dynamometer and the Kern hanging scale, to develop 2 procedures to measure forearm torque and lifting strength. Two assessors used the new techniques to test 15 healthy volunteers, 10 females and 5 males. Each assessor measured each participant on 3 occasions. Torque was tested for supination and pronation. Lifting strength was tested in 3 forearm positions, supinated, pronated, and neutral position. Analysis of reliability was performed using intraclass correlation coefficients (ICC), with 95% confidence intervals. As raters were fixed ICC model 3 was used with single measurements to determine consistency in agreement. Results: Torque: The intrarater reliability coefficients for test-retest observed for the Baseline dynamometer were for both raters between 0.96 and 0.97 for supination and 0.93 and 0.97 for pronation. There were no differences between the raters (P < .001). Lifting strength: The intrarater ICCs for the different forearm positions were nearly the same for both investigators (0.95-0.99) and similar values were noted for the interrater comparisons (0.95-0.98). Conclusions: Both the Baseline and Kern dynamometers demonstrated excellent intra- and interrater repeatability. The quality of measurements performed with our new methods is sufficient for future studies of forearm torque and lifting strength. Simple, yet reliable methods to quantify torque and lifting strength in a clinical setting have the potential to improve evaluations of wrist and forearm disorders as well as their treatments.