Sub-zero non-freezing of vascularized composite allografts in a rodent partial hindlimb model.

Ischemia is a major limiting factor in Vascularized Composite Allotransplantation (VCA) as irreversible muscular injury can occur after as early as 4-6 h of static cold storage (SCS). Organ preservation technologies have led to the development of storage protocols extending rat liver ex vivo preservation up to 4 days. Development of such a protocol for VCAs has the added challenge of inherent ice nucleating factors of the graft, therefore, this study focused on developing a robust protocol for VCA supercooling. Rodent partial hindlimbs underwent subnormothermic machine perfusion (SNMP) with several loading solutions, followed by a storage solution with cryoprotective agents (CPA) developed for VCAs. Storage occurred in suspended animation for 24h and VCAs were recovered using SNMP with modified Steen. This study shows a robust VCA supercooling preservation protocol in a rodent model. Further optimization is expected to allow for its application in a transplantation model, which would be a breakthrough in the field of VCA preservation.

Cartilage evaluation in finger joints in healthy controls and early hand osteoarthritis patients using high-resolution MRI.

OBJECTIVE: To compare direct evaluation of cartilage with high resolution MRI (hrMRI) to indirect cartilage evaluation using MRI inter-bone distance in hand OA patients and healthy controls. DESIGN: 41 hand OA patients and 18 healthy controls underwent hrMRI of the 2nd and 3rd metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints. The images were read by two independent readers using OMERACT hand OA MRI inter-bone distance score (0-3 scale) and a new hrMRI cartilage score with direct evaluation of the cartilage (0-3 scale). Inter-reader and intra-reader reliability was calculated using exact and close agreement and kappa values. The prevalence of abnormal scores and agreement between methods was assessed in both hand OA patients and healthy controls. RESULTS: The intra- and inter-reader reliability of both scores was comparable, with exact agreement in 73-83% and close agreement in 95-100%. In hand OA patients 27% of 161 joints had both cartilage damage and loss of inter-bone distance, cartilage damage by hrMRI only was present in 20% of joints and reduced inter-bone distance only in 4% of joints. In the healthy controls, 1 of 71 joints were scored as abnormal by both hrMRI and inter bone distance scoring, 1 joint was scored as abnormal using the hrMRI cartilage score only, whereas 15% of joints had only reduced inter bone distance. CONCLUSIONS: Direct cartilage evaluation of MCP and PIP joints using hrMRI has a good reliability, and the higher prevalence of hrMRI cartilage damage in hand OA patients and the lower prevalence in healthy controls in comparison to evaluation of inter-bone distance suggests a better validity.

Systematic review of treatments for diabetic peripheral neuropathy.

AIM: To evaluate treatment options for neuropathic pain and sensory symptoms resulting from diabetic peripheral neuropathy of the feet. METHODS: The databases PubMed, Embase and Web-of-Science were searched for randomized controlled trials, published in the period from database inception to 2 July 2015, that evaluated treatments for diabetic peripheral neuropathy of the feet with placebo or standard treatment as comparators. Participants in these trials included people with diabetes mellitus and diabetic peripheral neuropathy who were given any treatment for diabetic peripheral neuropathy. Risk of bias was assessed using the Delphi list of criteria. Data from the trials were extracted using standardized data extraction sheets by two authors independently. All analyses were performed using RevMan 5.2. In case of clinical homogeneity, statistical pooling was performed using a random effects model. RESULTS: This review included 27 trials on pharmacological, non-pharmacological and alternative treatments. In the meta-analysis of trials of α-lipoic acid versus placebo, total symptom score was reduced by -2.45 (95% CI -4.52; -0.39) with 600 mg i.v. α-lipoic acid (three trials), and was reduced by -1.95 (95% CI -2.89; -1.01) with 600 mg oral α-lipoic acid (two trials). Significant improvements in diabetic peripheral neuropathy symptoms were found with opioids, botulinum toxin A, mexidol, reflexology and Thai foot massage, but not with micronutrients, neurotrophic peptide ORG 2677 and photon stimulation therapy. CONCLUSION: In this review, we found that α-lipoic acid, opioids, botulinum toxin A, mexidol, reflexology and Thai foot massage had significant beneficial results.

Incidence and Risk Factors for Upper Extremity Climbing Injuries in Indoor Climbers.

The purpose of this study was to describe the prevalence, incidence and risk factors for climbing-related injuries of the upper extremities in recreational climbers. A total of 426 recreational climbers were recruited from indoor climbing halls. The baseline questionnaire included questions on potential risk factors for climbing injuries: personal factors, climbing-related factors and upper extremity injuries that had occurred in the previous 12 months. Follow-up questionnaires collected information on new injuries that occurred during the follow-up period. The incidence of climbing-related injuries during one-year follow-up was 42.4% with 13 injuries per 1000 h of climbing. The finger was the most frequently affected injury location (36.0%). The following risk factors were associated with the occurrence of upper extremity injuries: higher age (OR 1.03, 95% CI 1.01;1.05), performing a cooling-down (OR 2.02, 95% CI 1.28;3.18), climbing with campus board (OR 2.48, 95% CI 1.23;5.02), finger strength middle finger (OR 1.12, 95% CI 1.05;1.18) and previous injuries (OR 3.05, 95% CI 2.01;4.83). Climbing injuries of the upper body extremities are very common among recreational climbers in indoor halls and several risk factors can be identified that are related to a higher injury risk.

Enhancing Vascularized Composite Allograft Supercooling Preservation: A Multifaceted Approach with CPA Optimization, Thermal Tracking, and Stepwise Loading Techniques.

Vascularized composite allografts (VCAs) present unique challenges in transplant medicine, owing to their complex structure and vulnerability to ischemic injury. Innovative preservation techniques are crucial for extending the viability of these grafts, from procurement to transplantation. This study addresses these challenges by integrating cryoprotectant agent (CPA) optimization, advanced thermal tracking, and stepwise CPA loading strategies within an ex vivo rodent model. CPA optimization focused on various combinations, identifying those that effectively suppress ice nucleation while mitigating cytotoxicity. Thermal dynamics were monitored using invasive thermocouples and non-invasive FLIR imaging, yielding detailed temperature profiles crucial for managing warm ischemia time and optimizing cooling rates. The efficacy of stepwise CPA loading versus conventional flush protocols demonstrated that stepwise (un)loading significantly improved arterial resistance and weight change outcomes. In summary, this study presents comprehensive advancements in VCA preservation strategies, combining CPA optimization, precise thermal monitoring, and stepwise loading techniques. These findings hold potential implications for refining transplantation protocols and improving graft viability in VCA transplantation.

Supercooling preservation of vascularized composite allografts through CPA optimization, thermal tracking, and stepwise loading techniques.

Vascularized composite allografts (VCAs) present unique challenges in transplant medicine, owing to their complex structure and vulnerability to ischemic injury. Innovative preservation techniques are crucial for extending the viability of these grafts, from procurement to transplantation. This study addresses these challenges by integrating cryoprotectant agent (CPA) optimization, advanced thermal tracking, and stepwise CPA loading strategies within an ex vivo rodent model. CPA optimization focused on various combinations, identifying those that effectively suppress ice nucleation while mitigating cytotoxicity. Thermal dynamics were monitored using invasive thermocouples and non-invasive FLIR imaging, yielding detailed temperature profiles crucial for managing warm ischemia time and optimizing cooling rates. The efficacy of stepwise CPA loading versus conventional flush protocols demonstrated that stepwise (un)loading significantly improved arterial resistance and weight change outcomes. In summary, this study presents comprehensive advancements in VCA preservation strategies, combining CPA optimization, precise thermal monitoring, and stepwise loading techniques. These findings hold potential implications for refining transplantation protocols and improving graft viability in VCA transplantation.

Effect of Subnormothermic Machine Perfusion on the Preservation of Vascularized Composite Allografts After Prolonged Warm Ischemia.

BACKGROUND: Warm ischemia time (WIT) and ischemia-reperfusion injury are limiting factors for vascularized composite allograft (VCA) transplantation. Subnormothermic machine perfusion (SNMP) has demonstrated the potential to extend WIT in organ transplantation. This study evaluates the effect of SNMP on VCA viability after prolonged WIT. METHODS: Rat hindlimbs underwent WIT for 30, 45, 60, 120, 150, or 210 min, followed by 3-h SNMP. Monitoring of perfusion parameters and outflow determined the maximum WIT compatible with limb viability after SNMP. Thereafter, 2 groups were assessed: a control group with inbred transplantation (Txp) after 120 min of WIT and an experimental group that underwent WIT + SNMP + Txp. Graft appearance, blood gas, cytokine levels, and histology were assessed for 21 d. RESULTS: Based on potassium levels, the limit of WIT compatible with limb viability after SNMP is 120 min. Before this limit, SNMP reduces potassium and lactate levels of WIT grafts to the same level as fresh grafts. In vivo, the control group presented 80% graft necrosis, whereas the experimental group showed no necrosis, had better healing (P = 0.0004), and reduced histological muscle injury (P = 0.012). Results of blood analysis revealed lower lactate, potassium levels, and calcium levels (P = 0.048) in the experimental group. Both groups presented an increase in interleukin (IL)-10 and IL-1b/IL-1F2 with a return to baseline after 7 to 14 d. CONCLUSIONS: Our study establishes the limit of WIT compatible with VCA viability and demonstrates the effectiveness of SNMP in restoring a graft after WIT ex vivo and in vivo, locally and systemically.

How to treat Guyon's canal syndrome? Results from the European HANDGUIDE study: a multidisciplinary treatment guideline.

BACKGROUND: Although Guyon's canal syndrome is not highly prevalent, a considerable knowledge of anatomy is needed to localise and treat the pathology. Data on the effectiveness of interventions for this disorder are lacking. OBJECTIVE: To achieve consensus on a multidisciplinary treatment guideline for this disorder based on experts' opinions. METHODS: A European Delphi consensus strategy was initiated. In total, 35 experts (hand surgeons/hand therapists selected by the national member associations of their European federations and Physical Medicine and Rehabilitation physicians) participated in the Delphi consensus strategy. Each Delphi round consisted of a questionnaire, an analysis and a feedback report. RESULTS: After three Delphi rounds, consensus was achieved on the description, symptoms and diagnosis of Guyon's canal syndrome. The experts agreed that patients with this disorder should always receive instructions and that these instructions should be combined with another form of treatment. Instructions combined with splinting or with surgery were considered as suitable treatment options. Details on the use of instructions, splinting and surgery were described. Main factors for selecting one of the aforementioned treatment options were identified: severity and duration of the syndrome and previous treatments given. A relation between the severity/duration and choice of therapy was indicated by the experts and reported in the guideline. CONCLUSIONS: Although this disorder is less prevalent and not easy to diagnose, this guideline may contribute to better insight into and treatment of Guyon's canal syndrome.

Sural hypersensitivity after nerve transection depends on anatomical differences in the distal tibial nerve of mice and rats.

INTRODUCTION: Various mouse and rat models of neuropathic pain after nerve injury exist. Whilst some models involve a proximal nerve lesion or ligation of the sciatic trifurcation in mice and rats, others consists of a transection or ligation of distal nerves at the tibial bifurcation in mice or rats. The level of nerve cut directly affects the magnitude of hypersensitivity, and anatomical differences between mice and rats might therefore impact the development of hypersensitivity after distal tibial nerve transection as well. METHODS: The bifurcation of the distal tibial nerve into the medial and lateral plantar nerve (MPN and LPN), and the presence of anatomical differences in sural and tibial nerve distribution between mice and rat was evaluated. Sural mechanical sensitivity after transection of the MPN or whole tibial nerve was assessed using von Frey test until 8 weeks after surgery in 48 rats and 16 mice. RESULTS: The bifurcation of the tibial nerve into the MPN and LPN is situated proximal to the ankle in both mice and rats. The sural nerve joins the LPN in mice, but not in rats. A proximal communicating branch is present between the LPN and MPN in rats, but not in mice. MPN transection in mice caused hypersensitivity of the hindpaw innervated by the sural nerve, but not in rats. In rats, sural hypersensitivity only developed when both MPN and LPN were cut. CONCLUSION: Inter-species variation in nerve anatomy should be taken in consideration when performing surgery to induce plantar hypersensitivity in rodents.

Arthroscopic synovectomy versus intra-articular injection of corticosteroids for the management of refractory psoriatic or rheumatoid arthritis of the wrist: study protocol for a randomized controlled trial (ARCTIC trial).

BACKGROUND: Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) are inflammatory diseases that often affect the wrist and, when affected, can lead to impaired wrist function and progressive joint destruction if inadequately treated. Standard care consists primarily of disease-modifying anti-rheumatic drugs (DMARDs), often supported by systemic corticosteroids or intra-articular corticosteroid injections (IACSI). IACSI, despite their use worldwide, show poor response in a substantial group of patients. Arthroscopic synovectomy of the wrist is the surgical removal of synovitis with the goal to relieve pain and improve wrist function. The primary objective of this study is to evaluate wrist function following arthroscopic synovectomy compared to IACSI in therapy-resistant patients with rheumatoid or psoriatic arthritis. Secondary objectives include radiologic progress, disease activity, health-related quality of life, work participation and cost-effectiveness during a 1-year follow-up. METHODS: This protocol describes a prospective, randomized controlled trial. RA and PsA patients are eligible with prominent wrist synovitis objectified by a rheumatologist, not responding to at least 3 months of conventional DMARDs and naïve to biological DMARDs. For 90% power, an expected loss to follow-up of 5%, an expected difference in mean Patient-Rated Wrist Evaluation score (PRWE, range 0-100) of 11 and α = 0.05, a total sample size of 80 patients will be sufficient to detect an effect size. Patients are randomized in a 1:1 ratio for arthroscopic synovectomy with deposition of corticosteroids or for IACSI. Removed synovial tissue will be stored for an ancillary study on disease profiling. The primary outcome is wrist function, measured with the PRWE score after 3 months. Secondary outcomes include wrist mobility and grip strength, pain scores, DAS28, EQ-5D-5L, disease progression on ultrasound and radiographs, complications and secondary treatment. Additionally, a cost-effectiveness analysis will be performed, based on healthcare costs (iMCQ questionnaire) and productivity loss (iPCQ questionnaire). Follow-up will be scheduled at 3, 6 and 12 months. Patient burden is minimized by combining study visits with regular follow-ups. DISCUSSION: Persistent wrist arthritis continues to be a problem for patients with rheumatic joint disease leading to disability. This is the first randomized controlled trial to evaluate the effect, safety and feasibility of arthroscopic synovectomy of the wrist in these patients compared to IACSI. TRIAL REGISTRATION: Dutch trial registry (CCMO), NL74744.100.20. Registered on 30 November 2020. CLINICALTRIALS: gov NCT04755127. Registered after the start of inclusion on 15 February 2021.

Clinical variation in the treatment of trigger finger: An international survey of orthopaedic and plastic surgeons.

Trigger finger is a common condition affecting the hand. Therapeutic variability surrounds the management of trigger finger, especially in the mild cases. The aim of this study was to survey secondary care surgeons to describe the current management of trigger fingers. The steering group developed a survey for hand surgeons. Following piloting, the survey was distributed to hand surgeons in the United Kingdom and The Netherlands. A total of 713 plastic surgeons and orthopaedic surgeons were invited to participate in the online survey and 440 (62%) surgeons completed the survey. In both mild and moderate cases of trigger finger, steroid injection was the preferred treatment option. Open surgery was the treatment of choice for severe cases. However, there was variation in delivery of care, including type and dosage of steroid, site of injection, interval between injections, maximum number of injections, type of incision and treatment of patients with diabetes or rheumatoid arthritis. This highlights the need for a better evidence base for the treatment of trigger fingers.

Is there a difference in venous thrombosis rate in free flap anastomoses based on coupler diameter? A systematic review. Does Size Really Matter?

BACKGROUND: The adage is to use the largest anastomotic coupler device (coupler) size possible, since smaller an anastomosis might be more susceptible to thrombosis. It is unclear if this wisdom is supported by data. This study tests the hypothesis that there is no difference in the reported literature in thrombosis rate between different coupler sizes. METHODS: We searched PubMed, Embase, and the Cochrane Library. After screening 235 studies, we included 11 retrospective case-series. According to the criteria of Newcastle-Ottowa Scale, quality score ranged from 2 to 4 (out of 5) and funnel plots indicated publication bias. We included a total of 5930 coupled anastomoses. We calculated thrombosis rate per coupler diameter with exact confidence intervals (CIs). We regard non-overlapping CIs as a significant difference. RESULTS: Nine studies reported no difference in thrombosis rate based on coupler size. Two studies report a potentially greater thrombosis rates in smaller sizes: (1) 2.0 mm 27% (95% CI 17%-40%, 17/62 cases) vs. 3.0 mm 6.3% (95% CI 2.8%-12%, 8/126 cases) and (2) 1.5 mm 6.9% (95% CI 2.8%-14%, 7/101 cases) vs. 3.0 mm group 1.2% (95% CI 0.64%-2.1%, 13/1079). CONCLUSION: There is some evidence that suggests that smaller coupler sizes are associated with greater thrombosis rate, but the current available evidence has limitations. Performing a second anastomosis, in case, the first anastomosis is performed with a coupler size of 1.0, 1.5, or even 2.0 mm, can potentially reduce this rate, however, this remains to be determined.

Treatment and survival differences across tumor sites in malignant peripheral nerve sheath tumors: a SEER database analysis and review of the literature.

BACKGROUND: Currently, literature is scarce on differences across all possible tumor sites in malignant peripheral nerve sheath tumors (MPNSTs). To determine differences in treatment and survival across tumor sites and assess possible predictors for survival, we used the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: MPNST cases were obtained from the SEER database. Tumor sites were recoded into: intracranial, spinal, head and neck (H&N), limbs, core (thorax/abdomen/pelvis), and unknown site of origin. Patient and tumor characteristics, treatment modalities, and survival were extracted. Overall survival (OS) was assessed using univariable and multivariable Cox regression hazard models. Kaplan-Meier survival curves were constructed per tumor site for OS and disease-specific survival (DSS). RESULTS: A total of 3267 MPNST patients were registered from 1973 to 2013; 167 intracranial (5.1%), 119 spinal (3.6%), 449 H&N (13.7%), 1022 limb (31.3%), 1307 core (40.0%), and 203 unknown (6.2%). The largest tumors were found in core sites (80.0 mm, interquartile range [IQR]: 60.0-115.0 mm) and the smallest were intracranial (37.4 mm, IQR: 17.3-43.5 mm). Intracranial tumors were least frequently resected (58.1%), whereas spinal tumors were most often resected (83.0%). Radiation was administered in 35.5% to 41.8%. Independent factors associated with decreased survival were: older age, male sex, black race, no surgery, partial resection, large tumor size, high tumor grade, H&N site, and core site (all P < .05). Intracranial and pediatric tumors show superior survival (both P < .05). Intracranial tumors show superior OS and DSS curves, whereas core tumors have the worst (P < .001). CONCLUSION: Superior survival is seen in intracranial and pediatric MPNSTs. Core and H&N tumors have a worse prognosis.

Deletion of 1 amino acid in Indian hedgehog leads to brachydactylyA1.

Brachydactyly type A1 is a limb malformation characterized by a uniform shortening of the middle phalanges in all digits. Mutations in the Indian hedgehog (IHH) gene were shown to be the cause of this autosomal dominant disorder. The IHH protein is known to be an important signaling molecule involved in chondrocyte formation. So far, only missense mutations in IHH have been reported to cause BrachydactylyA1. We report here on the first deletion in IHH, p.delE95, causing mild BrachydactylyA1 in a small Dutch family. This brings the total number of different mutations found to cause BDA1 to 7.

[Arm injuries due to sport climbing]. / Blessures aan de arm bij sportklimmers.

There are 26 large climbing centres and 44 smaller indoor or outdoor climbing walls in The Netherlands at this time. Hand and finger injuries are the most common types of sport climbing injuries. Most injuries are caused by overstraining. Injuries include avulsion fractures, arthrosis, pulley rupture, damage to joint capsule and collateral ligaments, 'gamekeeper's thumb', 'climber's finger', lumbrical shift syndrome, 'climber's elbow', shoulder injuries and nerve compression syndromes. Treatment is usually conservative. Depending on the extent of damage surgical intervention may be indicated.

Modification of the use of the extensor retinaculum for reducible distal radioulnar joint instability: technique and results.

Different surgical techniques have been described for chronic distal radioulnar joint instability: they are often complicated, quite invasive and may not be recommended for bidirectional instability. We describe a procedure using a radial-based extensor retinaculum strip and a capsular plication. This is a simple technique and less invasive than 'anatomic' radioulnar ligament reconstructions. We report the results of 38 patients (38 wrists) who we treated. After a minimum of 8 months we quantified the outcomes of the patients objectively by assessing ranges of motion, grip strength and clinical assessment of stability, and subjectively using questionnaires. Overall, 36 out of 38 patients were stable after surgery. The operated forearm and wrist had approximately 3° less range of motion in all planes and 3 kgf less grip strength compared with the unoperated side. The median Mayo modified wrist score was 90; the median visual analogue scale score was 2. This surgical technique appears to successfully treat patients with chronic reducible distal radioulnar joint instability. Anatomic reconstruction of both radioulnar ligaments is not always necessary. LEVEL OF EVIDENCE: IV.

Comparison of assessment tools to score recovery of function after repair of traumatic lesions of the median nerve.

In this paper the recovery after repair of the median nerve has been used to compare different assessment tools for evaluation of peripheral nerve function: touch (moving 2-point discrimination (2PD); Semmes-Weinstein (SW) monofilament, motor (Medical Research Council (MRC) scale), combined motor and sensory (Dellon modification of the Moberg pick up test; Moberg Recognition test), and pain (visual analogue scale; pinprick-test). The mean (SD) age of our 28 patients was 28 (12) years. The mean (SD) follow-up period was 5 years, 2 months (2 years, 8 months). On the operated side three patients (11%) had a moving 2PD of less than 4 mm. The results of the moving 2PD were compared with those of the SW monofilaments, but with a poor correlation. The MRC score correlated well with opposition movement of the thumb and muscle wasting (p<0.01). We recommend a number of tests to evaluate (the chronological return of) peripheral nerve function.

Impairment and employment issues after nerve repair in the hand and forearm.

PURPOSE: To evaluate retrospectively subjective impairments, experienced disabilities, job and leisure restrictions and job changes in patients at least 2 years after repair of a peripheral nerve injury in the forearm, wrist or hand. METHODS: Between January 1,997 and January 2,000, 125 patients were treated surgically for a peripheral nerve injury in the hand and forearm at the Department of Plastic Surgery of a University Hospital. Sixty-one patients met the inclusion criteria. Using a questionnaire the ability to return to work (RTW), the possible consequences on Activities of Daily Life (ADL) and Instrumental Activities of Daily Life (IADL), job, hobby and housekeeping related disabilities and subjective pain were assessed. RESULTS: Forty of the 61 included patients returned the questionnaire. As a result of the injury, seven patients (19%) were not able to return to their own job and eight patients (20%) needed to quit or change their hobbies. Mean Time Off Work (TOW) was significantly longer (p=0.024) in non-digital nerve lesions (21.4 weeks) as compared to digital nerve lesions (9.5 weeks). CONCLUSIONS: From this study it was concluded that digital nerve lesions have little consequence on the ability to return to work and the time off work. However, the patients' hobbies are significantly affected. At least 2 years after the injury, the effects on ADL and IADL are minor.

The anatomical relationship of the superficial radial nerve and the lateral antebrachial cutaneous nerve: A possible factor in persistent neuropathic pain.

The superficial branch of the radial nerve (SBRN) is known for developing neuropathic pain syndromes after trauma. These pain syndromes can be hard to treat due to the involvement of other nerves in the forearm. When a nerve is cut, the Schwann cells, and also other cells in the distal segment of the transected nerve, produce the nerve growth factor (NGF) in the entire distal segment. If two nerves overlap anatomically, similar to the lateral antebrachial cutaneous nerve (LACN) and SBRN, the increase in secretion of NGF, which is mediated by the injured nerve, results in binding to the high-affinity NGF receptor, tyrosine kinase A (TrkA). This in turn leads to possible sprouting and morphological changes of uninjured fibers, which ultimately causes neuropathic pain. The aim of this study was to map the level of overlap between the SBRN and LACN. Twenty arms (five left and 15 right) were thoroughly dissected. Using a new analysis tool called CASAM (Computer Assisted Surgical Anatomy Mapping), the course of the SBRN and LACN could be compared visually. The distance between both nerves was measured at 5-mm increments, and the number of times they intersected was documented. In 81% of measurements, the distance between the nerves was >10 mm, and in 49% the distance was even <5 mm. In 95% of the dissected arms, the SBRN and LACN intersected. On average, they intersected 2.25 times. The close (anatomical) relationship between the LACN and the SBRN can be seen as a factor in the explanation of persistent neuropathic pain in patients with traumatic or iatrogenic lesion of the SBRN or the LACN.

Cerebral reorganisation of human hand movement following dynamic immobilisation.

Surgical treatment of a flexor tendon lesion of the hand is followed by a 6-week period of dynamic immobilisation. This is achieved by the elastic strings of a Kleinert splint, enabling only passive and no active flexor movements. After such immobilisation, the appearance of a temporary clumsy hand indicates decreased efficiency of cerebral motor control. Using PET we identified the recruitment of contralateral parietal and cingulate activations specifically related to the suboptimal character of these hand movements. After 6-8 weeks, normalised movement was related with contralateral putamen activation. Activations of the sensorimotor cortex and cerebellum were present during both scanning sessions. Changes in the pattern of cerebral activations reflect functional reorganisation. The shift from cortical to striatal involvement, observed in the group of four patients, generates the concept of unlearned movements being relearned.