Validation of cephalic index measurements in scaphocephaly.

INTRODUCTION: The cephalic index (CI) of the head can be measured manually using a caliper, the original technique, but it is also possible to determine it using skull X-ray, 2DCT and 3DCT images, 3D photo and with help of plagiocephalometry (PCM). PATIENTS AND METHODS: In this study, the manual caliper determination is statistically compared with other measuring methods for scaphocephaly patients (n = 39). RESULTS: The CI mean differences for the most representative data are sequentially 3.74, 2.16, 1.09 and 0.97 for the 2DCT, PCM, 3D photo and 3DCT techniques. The CI 2DCT values show a significant difference (p < 0.01) in reference to CI manually, while the other techniques show a p > 0.05. CONCLUSION: The conclusions are that significantly different results are achieved when using 2DCT relative to the manual caliper determination. No significant difference is observed between the 3D techniques and the manual method.

Gliding resistance of flexor tendon associated with carpal tunnel pressure: a biomechanical cadaver study.

The purpose of this study was to investigate the effect of carpal tunnel pressure on the gliding characteristics of flexor tendons within the carpal tunnel. Eight fresh human cadaver wrists and hands were used. A balloon was inserted into the carpal tunnel to elevate the pressure. The mean gliding resistance of the middle finger flexor digitorum superficialis tendon was measured with the following six conditions: (1) as a baseline, before balloon insertion; (2) balloon with 0 mmHg pressure; (3) 30 mmHg; (4) 60 mmHg; (5) 90 mmHg; (6) 120 mmHg. The gliding resistance of flexor tendon gradually increased as the carpal tunnel pressure was elevated. At pressures above 60 mmHg, the increase in gliding resistance became significant compared to the baseline condition. This study helps us to understand the relationship between carpal tunnel pressure, which is elevated in the patient with carpal tunnel syndrome (CTS) and tendon gliding resistance, which is a component of the work of flexion. These findings suggest that patients with CTS may have to expend more energy to accomplish specific motions, which may in turn affect symptoms of hand pain, weakness and fatigue, seen commonly in such patients.

Registration of 3-dimensional facial photographs for clinical use.

PURPOSE: To objectively evaluate treatment outcomes in oral and maxillofacial surgery, pre- and post-treatment 3-dimensional (3D) photographs of the patient's face can be registered. For clinical use, it is of great importance that this registration process is accurate (< 1 mm). The purpose of this study was to determine the accuracy of different registration procedures. MATERIALS AND METHODS: Fifteen volunteers (7 males, 8 females; mean age, 23.6 years; range, 21 to 26 years) were invited to participate in this study. Three-dimensional photographs were captured at 3 different times: baseline (T(0)), after 1 minute (T(1)), and 3 weeks later (T(2)). Furthermore, a 3D photograph of the volunteer laughing (T(L)) was acquired to investigate the effect of facial expression. Two different registration methods were used to register the photographs acquired at all different times: surface-based registration and reference-based registration. Within the surface-based registration, 2 different software packages (Maxilim [Medicim NV, Mechelen, Belgium] and 3dMD Patient [3dMD LLC, Atlanta, GA]) were used to register the 3D photographs acquired at the various times. The surface-based registration process was repeated with the preprocessed photographs. Reference-based registration (Maxilim) was performed twice by 2 observers investigating the inter- and intraobserver error. RESULTS: The mean registration errors are small for the 3D photographs at rest (0.39 mm for T(0)-T(1) and 0.52 mm for T(0)-T(2)). The mean registration error increased to 1.2 mm for the registration between the 3D photographs acquired at T(0) and T(L). The mean registration error for the reference-based method was 1.0 mm for T(0)-T(1), 1.1 mm for T(0)-T(2), and 1.5 mm for T(0) and T(L). The mean registration errors for the preprocessed photographs were even smaller (0.30 mm for T(0)-T(1), 0.42 mm for T(0)-T(2), and 1.2 mm for T(0) and T(L)). Furthermore, a strong correlation between the results of both software packages used for surface-based registration was found. The intra- and interobserver error for the reference-based registration method was found to be 1.2 and 1.0 mm, respectively. CONCLUSION: Surface-based registration is an accurate method to compare 3D photographs of the same individual at different times. When performing the registration procedure with the preprocessed photographs, the registration error decreases. No significant difference could be found between both software packages that were used to perform surface-based registration.

Incidence of cleft Lip and palate in the state of Andhra Pradesh, South India.

OBJECTIVE: To assess the incidence of cleft lip and palate defects in the state of Andhra Pradesh, India. DESIGN SETTING: The study was conducted in 2001 in the state of Andhra Pradesh, India. The state has a population of 76 million. Three districts, Cuddapah, Medak and Krishna, were identified for this study owing to their diversity. They were urban, semi-urban and rural, respectively. Literacy rates and consanguinity of the parents was elicited and was compared to national averages to find correlations to cleft births. Type and side of cleft were recorded to compare with other studies around the world and other parts of India. RESULTS: The birth rate of clefts was found to be 1.09 for every 1000 live births. This study found that 65% of the children born with clefts were males. The distribution of the type of cleft showed 33% had CL, 64% had CLP, 2% had CP and 1% had rare craniofacial clefts. Unilateral cleft lips were found in 79% of the patients. Of the unilateral cleft lips 64% were left sided. There was a significant correlation of children with clefts being born to parents who shared a consanguineous relationship and those who were illiterate with the odds ratio between 5.25 and 7.21 for consanguinity and between 1.55 and 5.85 for illiteracy, respectively. CONCLUSION: The birth rate of clefts was found to be comparable with other Asian studies, but lower than found in other studies in Caucasian populations and higher than in African populations. The incidence was found to be similar to other studies done in other parts of India. The distribution over the various types of cleft was comparable to that found in other studies.

Prenatal ultrasound diagnosis in 51 cases of holoprosencephaly: craniofacial anatomy, associated malformations, and genetics.

OBJECTIVE: To analyze the prenatal ultrasound findings of the craniofacial and extracephalic anatomy, the postnatal pathological findings, and the genetic anomalies in 51 cases of holoprosencephaly (HPE). MATERIALS AND METHODS: Between 1990 and 2005, a collective of 51 fetuses with tentative ultrasound diagnosis of HPE was recruited at two tertiary referral centers for prenatal ultrasound diagnostics via the Pia Fetal Database (GEMedical Systems, Webling, Germany). Cephalic as well as extracephalic anomalies were investigated, and all cases were subdivided into the subgroups lobar, a lobar, and semilobar HPE. In addition to the ultrasound investigation, 45 fetuses were analyzed for genetic anomalies and 21 fetuses underwent an autopsy. RESULTS: The average age at diagnosis was 21.9 weeks of gestation. There was a greater number of female fetuses, with an overall ratio of 2.67:1. In 61% of all cases, there was a reduction of growth in comparison with healthy fetuses of the same age. Within the second trimenon, the cephalic anomalies became evident when investigating the diameter of the fetal head (second trimenon: 71%below the fifth percentile; third trimenon: 92% below the fifth percentile). In 82%of the cases, extracephalic anomalies were diagnosed additionally. In 63%, the diagnosis of holoprosencephaly led to a termination of pregnancy. Ten percent of the fetuses were born alive. In 81% of the cases, the diagnosis of HPE was confirmed postnatally. The remaining 19% showed other severe cephalic and extracephalic anomalies. Chromosomal anomalies were detected in 79% of the fetuses, most frequently trisomy 13 (59%). DISCUSSION: Because of recent advances in the development and improvement of high-resolution ultrasound, early diagnosis of congenital anomalies such as HPE is now possible. In this study, which represents the largest collection of prenatally diagnosed HPE reported in the literature to date, the average age at diagnosis was earlier than in other studies. The ultrasound devices of today provide excellent images of the fetus that allow an exact diagnosis of craniomaxillofacial anomalies as well as extracephalic anomalies. Apart from a very few cases, the diagnosis of HPE is incompatible with life.

Dextrose-induced subsynovial connective tissue fibrosis in the rabbit carpal tunnel: A potential model to study carpal tunnel syndrome?

In this pilot study, hypertonic dextrose solution was used to induce fibrosis of the subsynovial connective tissue (SSCT) and create an animal model of potential use in the study of carpal tunnel syndrome (CTS). The SSCT of the carpal tunnel in 15 New Zealand white rabbits were injected with 0.05 ml of 10% dextrose solution in 1 paw and 0.05 ml of saline in the contralateral paw, to serve as a control. The animals were killed at 1, 2, 4, 8, or 12 weeks. While the saline side showed minimal changes at any time period, the hypertonic dextrose side showed progressive noninflammatory SSCT fibrosis, with vascular proliferation and thickening of collagen bundles. Demyelination of the median nerve developed at 12 weeks after the injection on the dextrose side. These findings are similar to the progression of pathology noted in humans with CTS.

Flexor tendon and synovial gliding during simultaneous and single digit flexion in idiopathic carpal tunnel syndrome.

The characteristic pathological finding in carpal tunnel syndrome (CTS) is non-inflammatory fibrosis of the subsynovial connective tissue (SSCT), which lies between the flexor tendons and the visceral synovium (VS). How this fibrosis might affect tendon function is unknown. To better understand the normal function of the SSCT, the relative motion of the middle finger flexor digitorum superficialis (FDS III) tendon and VS was observed during finger flexion in patients with CTS and cadavers with a history of CTS and compared to normal cadavers. A digital camcorder was used to monitor the gliding motion of the FDS III tendon and SSCT in eight patients with idiopathic CTS undergoing carpal tunnel release surgery (CTR), in eight cadavers with an antemortem history of CTS and compared these with eight cadaver controls. There were no significant differences noted in the total movement of the SSCT relative to the FDS III. However, the pattern of SSCT movement relative to the FDS III in the CTS patients and cadavers with an antemortem history of CTS differed from the controls in one of two patterns, reflecting either increased SSCT adherence to FDS III or increased SSCT dissociation from FDS III. In CTS, the gliding characteristics of the SSCT are qualitatively altered. These changes may be the result of increased fibrosis within the SSCT, which in some cases has ruptured, resulting in SSCT-tendon dissociation. Similar changes are also identified postmortem in the CTS patient.

Impairment and disability after severe hand injuries with multiple phalangeal fractures.

PURPOSE: Upper-extremity impairment evaluation is performed mostly by using guidelines provided by the American Medical Association (AMA). Recently, subjective disability tests, such as the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire, have been developed that appreciate the limitations patients experience in everyday life. In this study, the correlation between impairment and disability was assessed after treatment for severe hand injuries with multiple phalangeal fractures, with adjustment for comorbidity and follow-up duration. METHODS: The functional recovery of patients suffering severe hand trauma was evaluated using AMA impairment rating tests and DASH disability questionnaire scores. RESULTS: Seventy-eight patients with 228 phalangeal fractures were available for testing, with a mean follow-up period of 7.5 years. No statistically significant correlation existed between the AMA impairment ratings for the hand and the DASH module scores. There were weak correlations between the AMA impairment ratings for the arm and total body and the DASH module function scores. CONCLUSIONS: The lack of a strong correlation emphasizes the clear distinction between impairment and disability. The inclusion of disability outcome measures in the evaluation of hand trauma regimens might help to expand the clinician's view to more individualized, activity-of-daily-living-oriented, treatment regimens.

Gliding characteristics of flexor tendon and tenosynovium in carpal tunnel syndrome: a pilot study.

The characteristic pathological finding in carpal tunnel syndrome (CTS) is noninflammatory fibrosis of the synovium. How this fibrosis might affect tendon function, if at all, is unknown. The subsynovial connective tissue (SSCT) lies between the flexor tendons and the visceral synovium (VS) of the ulnar tenosynovial bursa. Fibrosis of the SSCT may well affect its gliding characteristics. To investigate this possibility, the relative motion of the flexor tendon and VS was observed during finger flexion in patients undergoing carpal tunnel surgery, and for comparison in hands without CTS, in an in vitro cadaver model. We used a camera to document the gliding motion of the middle finger flexor digitorum superficialis (FDS III) tendon and SSCT in three patients with CTS during carpal tunnel release and compared this with simulated active flexion in three cadavers with no antemortem history of CTS. The data were digitized with the use of Analyze Software (Biomedical Imaging Resource, Mayo Clinic, Rochester, MN). In the CTS patients, the SSCT moved en bloc with the tendon, whereas, in the controls the SSCT moved smoothly and separately from the tendon. The ratio of VS to tendon motion was higher for the patients than in the cadaver controls. These findings suggest that in patients with CTS the synovial fibrosis has altered the gliding characteristics of the SSCT. The alterations in the gliding characteristics of the SSCT may affect the ability of the tendons in the carpal tunnel to glide independently from each other, or from the nearby median nerve. These abnormal tendon mechanics may play a role in the etiology of CTS.

Gliding characteristics between flexor tendons and surrounding tissues in the carpal tunnel: a biomechanical cadaver study.

The purpose of this study was to investigate the gliding characteristics of flexor tendons within the carpal tunnel with varied wrist positions and tendon motion styles, which may help us to understand the relationship between carpal tunnel syndrome (CTS) and repetitive hand motion. Eight fresh human cadaveric wrists and hands were used. The peak (PGR) and mean (MGR) gliding resistance of the middle finger flexor digitorum superficialis tendon were measured with the wrist in 0, 30, and 60 degrees of flexion and extension. While moving all three fingers together, the PGR at 60 degrees flexion was significantly higher than that at 0, 30, or 60 degrees extension. While moving the middle finger alone, the PGR at 60 and 30 degrees flexion was significantly higher than the PGR at 60 degrees extension. The PGR moving the middle finger FDS alone was significantly greater than that for all three digits moving together in 0, 30, and 60 degrees flexion. Differential finger motion with wrist flexion elevated the tendon gliding resistance in the carpal tunnel, which may be relevant in considering the possible role of wrist position and activity in the etiology of CTS.

Changes in the functional structure of the tenosynovium in idiopathic carpal tunnel syndrome: a scanning electron microscope study.

BACKGROUND: The subsynovial connective tissue lies between the flexor tendons and visceral synovium in the carpal tunnel. Although tenosynovial fibrosis is nearly universally noted in patients with carpal tunnel syndrome, the relationship, if any, between the fibrosis and nerve abnormalities is unknown. The authors used light and scanning electron microscope imaging of the subsynovial connective tissue to gather information about its organization. METHODS: Human subsynovial connective tissue was studied to determine its ultrastructural morphology. Biopsy specimens of 11 patients (12 hands) with idiopathic carpal tunnel syndrome, 14 cadaver controls, and two cadavers with a history of carpal tunnel syndrome were obtained for scanning electron microscopic imaging and histopathologic examination. RESULTS: The visceral synovial layer is an uninterrupted membrane that defines the bursa dorsally. The subsynovial connective tissue consists of fibrous bundles that run parallel to the tendon, interconnected by smaller fibrous fibers. It connects to the synovial membrane and the flexor tendons. During tendon motion, the loose fibers between adjacent layers are stretched. The control tissue showed interconnections between all the parallel layers, whereas in patients with idiopathic carpal tunnel syndrome, these interconnections were absent, replaced with thicker parallel fibrous bundles. Similar changes were found in the cadaver carpal tunnel syndrome specimens. Pathologic changes in the patient and cadaver carpal tunnel syndrome specimens were most apparent close to the tendon and became progressively less severe in more superficial layers. CONCLUSIONS: The authors' observation that the most severe changes in the subsynovial connective tissue were found close to the tendon suggests that these changes may be the result of a shearing injury.

Surface treatment of flexor tendon autografts with carbodiimide-derivatized hyaluronic Acid. An in vivo canine model.

BACKGROUND: Clinical and experimental studies have demonstrated that restrictive adhesions and poor digital motion are common complications after extrasynovial tendon grafting in an intrasynovial environment. The purpose of this study was to test the hypothesis that surface modification of an extrasynovial tendon with use of a carbodiimide-derivatized hyaluronic acid-gelatin polymer (cd-HA) improves gliding ability and digital function after tendon grafting in a canine model in vivo. METHODS: The peroneus longus tendons from both hindpaws of twenty-four dogs were harvested and transplanted to replace the flexor digitorum profundus tendons in the second and fifth digits of one forepaw. Prior to grafting, one of the peroneus longus tendons was coated with cd-HA, which consists of 1% hyaluronic acid, 10% gelatin, 0.25% 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), and 0.25% N-hydroxysuccinimide (NHS), while the other was immersed in saline solution only. Eight dogs were killed at one, three, and six weeks. Digital normalized work of flexion, tendon gliding resistance, and hyaluronic acid quantification (with the hyaluronic acid-binding-protein staining technique) were the outcome measures. RESULTS: The normalized work of flexion of the tendons treated with cd-HA was significantly lower than that of the saline-solution-treated controls at each time-point (p < 0.05). The gliding resistance of the cd-HA group was significantly lower than that of the saline-solution group at three and six weeks (p < 0.05). The ratio between the intensity of staining of the cd-HA-treated tendons with that of the saline-solution-treated controls was significantly greater at time-0 than at three or six weeks (p < 0.05), but there was no significant difference between time-0 and one-week values. CONCLUSIONS: Treating the surface of an extrasynovial tendon autograft with a carbodiimide-derivatized hyaluronic acid-gelatin polymer decreases digital work of flexion and tendon gliding resistance in this flexor tendon graft model in vivo. CLINICAL RELEVANCE: cd-HA gelatin may provide surgeons with a new and useful method to improve the quality of tendon graft surgery.

Surgery versus conservative therapy in carpal tunnel syndrome in people aged 70 years and older.

BACKGROUND: Carpal tunnel syndrome is common in the general population, with a prevalence that increases with age. Although good satisfaction has been described after carpal tunnel release, little is known about the long-term outcome of treatment in elderly individuals with carpal tunnel syndrome. METHODS: The authors reviewed data from a population-based sample of 102 patients aged 70 years and older with carpal tunnel syndrome. They used valid and sensitive mailed follow-up outcome [Boston Carpal Tunnel, satisfaction (American Academy of Orthopaedic Surgeons), and health status (Short Form-36) questionnaires to assess symptoms, functional status, expectations of treatment, and satisfaction with the results at a minimum of 2 years after initial diagnosis. RESULTS: Seventy patients with a mean age of 77.0 years (range, 70.2 to 88.5 years) responded to the survey, with a mean follow-up of 4.8 years. Patients who had surgery were more likely to have had more severe disease than those treated nonoperatively (Mantel-Haentzel test, p < 0.001). Satisfaction was 93 percent after surgical treatment and 54 percent after nonsurgical treatment. Patients who had surgery had significantly better relief of symptoms (t test, p < 0.01), functional status (t test, p < 0.05), satisfaction (t test, p < 0.001), and expectations with treatment (t test, p < 0.05) scores as compared with those who had nonsurgical treatment. CONCLUSIONS: In patients over the age of 70, surgery appears to be associated with better symptom relief, functional status, satisfaction, and expectations with treatment than nonoperative therapy does. Age should not be considered a contraindication for carpal tunnel surgery, nor should nonoperative therapy be favored in this age group.

High-resolution ultrasound analysis of subsynovial connective tissue in human cadaver carpal tunnel.

The carpal tunnel contains the median nerve, nine flexor tendons, two synovial bursae, and peritendinous subsynovial connective tissue (SSCT). Fibrosis of the SSCT is the most consistent pathological finding in patients with carpal tunnel syndrome. We investigated the anatomy and gliding characteristics of the flexor digitorum superficialis tendon and its adjacent SSCT with high-resolution ultrasound (15 MHz). Our hypotheses were that tendon and SSCT are distinguishable by ultrasound and that their velocities during tendon excursion are different. Qualitative ultrasound analysis of a flexor tendon and its SSCT was performed on five cadaver wrists and correlated to respective findings after anatomical study of the same cadavers. Quantitative Doppler velocity analysis of eight cadaver wrists was done to assess the sliding movement of the tendon and its SSCT within the carpal tunnel. No significant difference was found between the thickness of SSCT measured by ultrasound and that measured directly after dissection. The SSCT moved slower than its flexor tendon. The SSCT velocities were statistically different from the tendon velocities (t-test, p>0.001). High-resolution ultrasound is a very precise method to display the anatomy of the tendon and SSCT within the carpal tunnel, and their different velocities can be detected with Doppler. Noninvasive assessment of the thickness and velocity of the tenosynovium in carpal tunnel syndrome by high-resolution sonography might be a new diagnostic tool for disorders affecting the SSCT, especially carpal tunnel syndrome.

Tensile strength of a new suture for fixation of tendon grafts when using a weave technique.

PURPOSE: To evaluate a new corner stitch construct for tendon graft or tendon transfer fixation and compare the tensile strength with a conventional central cross-suture design in human cadaver tendons. METHODS: Flexor digitorum profundus tendons of the index, middle, and ring fingers (48 total) were used as recipients and palmaris longus, extensor indicis proprius, and extensor digitorum communis tendons of the index finger (48 total) were used as grafts from 16 fresh-frozen human cadaver hands. We compared the cross-stitch technique with a new corner stitch technique in tendon repairs made with 1, 2, or 3 weaves (8 per group). Tendons were sutured at each weave with either 2 full-thickness cross-stitches or 4 partial-thickness corner stitches of 4-0 nylon. Mattress sutures also were placed through the free tendon end for each repair type. The tensile strength of the tendon-graft composite was measured with a materials testing machine. RESULTS: The tensile strength of the repairs increased significantly with the number of weaves. When 2 or 3 weaves were used with the corner stitch or when 3 weaves were used with the cross-stitch, the repairs were significantly stronger. Although no significant difference in strength to failure was noted when comparing cross and corner stitches with equivalent numbers of weaves, qualitatively there was a difference in mode of failure with the 3-weave corner stitches failing primarily by intrasubstance tendon failure and the 3-weave cross-stitch repairs failing by tendon pullout. CONCLUSIONS: The corner stitch is as strong as conventional cross-stitch repairs and its superficial placement may be more favorable to tendon blood supply. This repair may be advantageous for clinical applications.

Comparative anatomy of the subsynovial connective tissue in the carpal tunnel of the rat, rabbit, dog, baboon, and human.

The tenosynovium in the human carpal tunnel is connected to the flexor tendons and the median nerve by the subsynovial connective tissue (SSCT). The most common histological finding in carpal tunnel syndrome (CTS), a compression neuropathy of the median nerve, is noninflammatory fibrosis of the SSCT. The relationship, if any, between the fibrosis and nerve pathology is unknown, although some have speculated that a change in the SSCT volume or stiffness might be the source of the compression. Yet, while animal models have been used to study the physiology of nerve compression, so far none have been used to study the relationship of the SSCT pathology to the neurophysiological abnormalities. The purpose of this study was to identify animal models that might be appropriate to study the interaction of SSCT and nerve function in the development of CTS. The front paws of a rat, rabbit, dog, and baboon were dissected. The carpal tunnel anatomy and SSCT of these animals were also examined by light and scanning microscopy and compared to the relevant human anatomy and ultrastructure. The carpal tunnel anatomy and contents of the baboon and rabbit are similar to humans. The canine carpal tunnel lacks the superficial flexor tendons and the rat carpal tunnel is very small. The human, baboon, and rabbit specimens had very similar organization of the SSCT, and content of the carpal canal. We conclude that, while both the baboon and rabbit would be good animal models to study the relationship of the SSCT to CTS, the rabbit is likely to be more practical, in terms of cost and animal care concerns.

Functional outcome after surgical treatment of phalangeal fractures in severely injured hands.

We assessed functional results after treatment of phalangeal fractures in severely injured hands. Our aim was to quantify digital functional loss with (combinations of) risk factors of unsatisfactory function. Patients who had multiple phalangeal fractures necessitating operation in a 10-year time period were tested, using measurements of total active movement. Seventy-eight patients with 228 phalangeal fractures were available for follow-up. In 88 fingers, the fractures ended in amputation and were excluded from the study. In the resulting 140 fractures, 74 (53%) had a good result (movement >180degrees for fingers 2-5, and >98degrees for the thumb), and 66 (47%) in an unsatisfactory result. Associated soft tissue injury, level of injury, and arthrodesis were risk factors for diminished function. Intra-articular fractures and multiple fractures within the same finger predisposed to arthrodesis. Despite the extensive and severe injuries more than half had good results, which is comparable with reports describing hand injuries with less extensive trauma.

Short-term assessment of optimal timing for postoperative rehabilitation after flexor digitorum profundus tendon repair in a canine model.

Abstract The purpose of this study was to compare the short-term outcome following flexor tendon repair for postoperative rehabilitation commencing on day 1 (a common clinical choice) versus day 5 (the day on which, with postoperative immobilization, the initial gliding resistance is least in this model) in an in vivo canine model. Work of flexion (WOF) and tendon strength were evaluated following tendon laceration and repair in 24 dogs sacrificed 10 days postoperatively. Starting postoperative mobilization at day 5 resulted in no tendon ruptures compared with tendon ruptures in four of the dogs (33%) in the group subjected to mobilization starting at day 1. While there was no statistically significant difference in WOF between groups at day 10, there was a trend toward lower resistance favoring the day 5 start group, and the statistical power to detect a difference in WOF was diminished by the ruptures in the day 1 group. We conclude that starting rehabilitation on day 5, when initial gliding resistance is lower, may have an advantage over earlier starting times, when surgical edema and other factors increase the initial force requirements to initiate tendon gliding. We plan further studies to evaluate the longer-term benefits of this rehabilitation program.

A histological and immunohistochemical study of the subsynovial connective tissue in idiopathic carpal tunnel syndrome.

BACKGROUND: The most common histological finding in carpal tunnel syndrome is noninflammatory synovial fibrosis. The accumulated effect of minor injuries is believed to be an important etiologic factor in some cases of carpal tunnel syndrome. We sought evidence of such injuries in the synovial tissue of patients with carpal tunnel syndrome and in cadaver controls. METHODS: We compared synovial specimens from thirty patients who had idiopathic carpal tunnel syndrome with specimens from a control group of ten fresh-frozen cadavers of individuals who had not had an antemortem diagnosis of carpal tunnel syndrome and who met the same exclusion criteria. Analysis included histological and immunohistochemical examination for the distribution of collagen types I, II, III, and VI and transforming growth factor-beta (TGF-beta) RI, RII, and RIII. RESULTS: Histological examination showed a marked increase in fibroblast density, collagen fiber size, and vascular proliferation in the specimens from the patients compared with the control specimens (p < 0.001). Collagen types I and II were not found in the synovium of either the patients or the controls, but collagen type VI was a major component of both. Collagen type-III fibers were more abundant in the patients than in the controls (p < 0.001). Expression of TGF-beta RI was found in the endothelial cells and fibroblasts in the patient and control specimens, with a marked increase in expression in the fibroblasts of the patients compared with that in the control tissue (p < 0.001). CONCLUSIONS: These findings are similar to those after injury to skin, tendon, and ligament and suggest that patients with idiopathic carpal tunnel syndrome may have sustained an injury to the subsynovial connective tissue.