Advertisement for orthosearch.org.uk
Results 1 - 20 of 25
Results per page:
Bone & Joint 360
Vol. 12, Issue 5 | Pages 27 - 30
1 Oct 2023

The October 2023 Wrist & Hand Roundup. 360. looks at: Distal radius fracture management: surgeon factors markedly influence decision-making; Fracture-dislocation of the radiocarpal joint: bony and capsuloligamentar management, outcomes, and long-term complications; Exploring the role of artificial intelligence chatbot in the management of scaphoid fractures; Role of ultrasonography for evaluation of nerve recovery in repaired median nerve lacerations; Four weeks versus six weeks of immobilization in a cast following closed reduction for displaced distal radial fractures in adult patients: a multicentre randomized controlled trial; Rehabilitation following flexor tendon injury in Zone 2: a randomized controlled study; On the road again: return to driving following minor hand surgery; Open versus single- or dual-portal endoscopic carpal tunnel release: a meta-analysis of randomized controlled trials


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_13 | Pages 91 - 91
1 Nov 2021
Aljasim O Yener C Demirkoparan M Bilge O Küçük L Gunay H
Full Access

Introduction and Objective. Zone 2 flexor tendon injuries are still one of the challenges for hand surgeons. It is not always possible to achieve perfect results in hand functions after these injuries. There is no consensus in the literature regarding the treatment of zone 2 flexor tendon injuries, tendon repair and surgical technique to be applied to the A2 pulley. The narrow fibro-osseous canal structure in zone 2 can cause adhesions and loss of motion due to the increase in tendon volume due to surgical repair. Different surgical techniques have been defined to prevent this situation. In our study, in the treatment of zone 2 flexor tendon injuries; Among the surgical techniques to be performed in addition to FDP tendon repair; We aimed to compare the biomechanical results of single FDS slip repair, A2 pulley release and two different pulley plasty methods (Kapandji and V-Y pulley plasty). Materials and Methods. In our study, 12 human upper extremity cadavers preserved with modified Larssen solution (MLS) and amputated at the mid ½ level of the arm were used. A total of 36 fingers (second, third and the fourth fingers were used for each cadaver) were divided into four groups and 9 fingers were used for each group. With the finger fully flexed, the FDS and FDP tendons were cut right in the middle of the A2 pulley and repaired with the cruciate four-strand technique. The surgical techniques described above were applied to the groups. Photographs of fingers with different loads (50 – 700 gr) were taken before and after the application. Proximal interphalangeal (PIP) joint angle, PIP joint maximum flexion angle and bowstring distance were measured. The gliding coefficient was calculated by applying the PIP joint angle to the single-phase exponential association equation. Results. Gliding coefficient after repair increased by %21.46 ± 44.41, %62.71 ± 116.9, %26.8 ± 35.35 and %20.39 ± 28.78 in single FDS slip repair, A2 pulley release, V-Y pulley plasty and Kapandji plasty respectively. The gliding coefficient increased significantly in all groups after surgical applications (p<0.05). PIP joint maximum flexion angle decreased by %3.17 ± 7.92, %12.82 ± 10.94, %8.33 ± 3.29 and %7.35 ± 5.02 in single FDS slip repair, A2 pulley release, V-Y pulley plasty and Kapandji plasty respectively. PIP joint maximum flexion angle decreased significantly after surgery in all groups (p<0.05). However, there was no statistically significant difference between surgical techniques for gliding coefficient and PIP joint maximum flexion angle. Bowstring distance between single FDS slip repair, kapandji pulley plasty and V-Y pulley plasty showed no significant difference in most loads (p>0.05). Bowstring distance was significantly increased in the A2 pulley release group compared to the other three groups (p<0.05). Conclusion. Digital motion was negatively affected after flexor tendon repair. Similar results were found in terms of gliding coefficient and maximum flexion angle among different surgical methods. As single FDS slipe repair preserves the anatomical structure of the A2 pulley therefore we prefer it as an ideal method for zone 2 flexor tendon repair. However, resection of FDS slip may jeopardizes nutrition to the flexor digitorum profundus tendon which weakens the repair site. Therefore the results must be confirmed by an in vivo study before a clinical recommendation can be made. Keywords: Flexor tendon; injury; pulley plasty; cadaver;


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_15 | Pages 4 - 4
7 Nov 2023
Tshisikule R
Full Access

Our study sought to establish the necessity of prolonged pre-operative antibiotic prophylaxis in patients presenting with zone II and zone V acute flexor tendon injuries (FTI). We hypothesized that a single dose of prophylactic antibiotic was adequate in prevention of post-operative wound infection in acute zone II and V FTI. This was a prospective study of 116 patients who presented with zone II and zone V acute FTI. The study included patients who were 18 years and older. Those with macroscopic contamination, immunocompromised, open fractures, bite injuries, and crush injuries were excluded. Patients were randomised into a group receiving a single dose of prophylactic antibiotic and another group receiving a continuous 8 hourly antibiotic doses until the day of surgery. Each group was subdivided into occupational and non-occupational injuries. Their post-operative wound outcomes were documented 10 – 14 days after surgery. The wound outcome was reported as no infection, superficial infection (treated with wound dressings), and deep infection (requiring surgical debridement). There was 0.9% rate of deep post-operative wound infections, which was a single zone V acute FTI case in a single dose prophylactic antibiotic group. There was a 7.8% superficial post-operative wound infection rate, which was mainly zone II acute FTI in both antibiotic groups. There was a strong association between zone II acute FTI and post-operative wound infection (p < 0.05). There was no association between (antibiotic dosage or place of injury) with post-operative wound infection (p > 0.05). There is no benefit in prescribing prolonged pre-operative antibiotic in patients with acute, simple lacerations to zone II and zone V FTI if there is no macroscopic wound contamination


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_15 | Pages 3 - 3
7 Nov 2023
Leslie K Matshidza S
Full Access

Intimate partner violence (IPV) causes significant morbidity and its unlikely to be reported compared to other forms of gender-based violence (GBV). For early detection, understanding Orthopaedic injuries from GBV is vital. This study assesses the pattern of musculoskeletal injuries from GBV and determines the factors associated with it. It is a retrospective observational study of patients aged ≥18 years, with GBV-related acute Orthopaedic injuries. Data was reviewed from January 2021 to December 2021, including, demographic information, soft tissue and bony injuries, relationship to assailant, substance abuse and the day and time of injury. Frequencies and percentages for categorical data were analysed. Chi-square test was used to calculate association. T-test was used to compare groups for continuous & categorical variables. Multivariate analysis was conducted to find the odds ratio and a p-value <0.05 was statistically significant. 138 patients were included, the mean age at presentation being 35.02 years (SD=11). 92.75% of GBV victims were females. Most were unemployed (66.7%). 30.43% (n-42) had a soft tissue injury; superficial laceration being the most common (23.1%), flexor tendon injury (10.87%), hand abscess (5.8%), and extensor tendon injury (5.07%). 71.02 % (n=98) sustained appendicular fractures. 51.45% (n=71) sustained upper limb fractures; distal radius fractures (10.86%) and distal 3rd ulnar fractures (9,42%). 19.57% (n=27) had lower limb fractures; 7.25% (n=10) had lateral malleolus ankle fractures. 63.7% (n=80) of cases were by an intimate partner on weekends (50.73%). 62.31% occurred between 16h00 and 0h00. 41.1% (n=65) reported alcohol abuse. 63.04% had surgery. GBV likely occurs in early middle-aged females by intimate partners influenced by alcohol over the weekends between 16h00 to 0h00. Distal radius/distal 3rd ulnar fractures are the most common bony injuries. Superficial wrist laceration is the commonest soft tissue injury. These findings may assist with early detection and intervention to prevent adverse outcomes in GBV


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 463 - 463
1 Sep 2012
Gaskin J Forde-Gaskin D Ajekigbe L
Full Access

Introduction. Flexor tendon injuries are quite common injuries. They can result in persisting functional deficit if not repaired and appropriately rehabilitated. We look at flexor tendon injuries over a period of 1 year and re-audited three years later. Method. We audited all flexor tendon injuries that were treated at our institution and repeated the same audit three years after. We looked at various aspects of the injuries including the site injured, the zone of injury, other structures injured, the type of repair and material used as well as the rehabilitation regime. Results. The initial audit had 43 patients, 83% male, 55% unemployed with 85 tendon injuries. There were 35% zone 5 injuries with 34% repaired in <24hrs with modified Kessler core 3.0 prolene sutures and 6.0 prolene peripheral sutures. The rupture rate was 3% and the infection rate was 1%. A re-audited was done 3 years later, over the same time period, there were 69 patients, 83% male, 1% unemployed with 102 tendon injuries. There were 40% zone 2 injuries with 43% repaired with modified Kessler core 3.0 prolene sutures and 6.0 prolene peripheral sutures. Rupture rate was 9% and infection rate was 1% and 10% median nerve injury. All injuries were rehabilitated using the Belfast regime. Discussion and Conclusion. Flexor tendon injuries are frequently occurring injuries and require a careful and meticulous attention to detail, relative to repair, to achieve the most effective recovery. We found that over a three year period that the zone of injury in the cohort of patients in our region had changed, as well as the unemployment rate. Other parameters were generally similar. We conclude that treatment of flexor tendon injuries should undergo the audit cycle to ensure that best practice is achieved and maintained


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIII | Pages 56 - 56
1 May 2012
Patel M O'Donnell T
Full Access

Increased use of locking volar plates for distal radius fractures led to a number of reports in literature of flexor tendon injuries from impingement and attrition against hardware. Repair of the pronator quadratus is critical in preventing tendon injury. We present a pronator quadratus sparing approach to the distal radius. The senior author has used a pronator quadratus sparing lateral pillar approach for for the past five years. A lateral incision is used over the radial styloid. The first dorsal compartment is released and APL and EPB tendons retracted. The underlying brachio-radialis tendon and insertion fascia is split and the palmar portion elevated off the distal radius with the pronator quadratus as a single contiguous sheet. The distal edge of the pronator quadratus is elevated from the wrist capsule by sharp dissection. The radial artery is protected by the retracted tissue. Repair of the brachio-radialis tendon and insertion fascia is much more robust than that of the pronator quadratus covering the entire plate. Since 2004, the senior author has used the pronator quadratus sparing approach for volar plating of the distal radius, in 183 cases. At last follow-up there were no instances of flexor tendon injury, which was considered to be one of the outcome measures and end-points. There was no impingement in the first dorsal compartment, except in two cases of lateral pillar hardware impingement from additional lateral pillar plate fixation through the same approach. Nine cases had minor persistent superficial radial nerve parasthesia. One case had a superficial wound infection requiring drainage. The repaired pronator quadratus formed a barrier protecting the plate. The infection was aggressively treated and the plate left in situ for three months till fracture union. Cultures from the retrieved plate showed no organisms. Another implant had two of the locking screws back out. The pronator quadratus fascia was tented with an underlying haematoma. The fascia however only showed minimum screw penetration and no flexor tendon injury. Average wrist dorsiflexion was 72 deg and palmar flexion 65 deg. Average pronation was 81 deg and average supination 69 deg. Supination range was slow to recover in younger patients. One explanation could be the tight pronator quadratus repair. Average PRWE and DASH scores were 19. The quadratus sparing approach to the volar distal radius is easy to perform and protects the flexor tendons at the wrist. Cases demonstrated that an intact pronator quadratus can act as an effective barrier to prominent hardware and superficial infection. Supination range may be reduced by this approach due to a tight repair, though a palmar DRUJ capsule contracture may also be an explanation


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_II | Pages 22 - 22
1 Feb 2012
Rafee A Muhammed A Sulaiman M
Full Access

Percutaneous A1 pulley release is being increasingly used as an alternative to open surgical release and injection of local steroids for the treatment of the trigger digit. We treated 43 patients, average age 57 years (range12-78). All trigger digits were grade III-IV (Quinnell classification). A mean duration of pre-operative symptoms was 7.3 months (range 2-13 months). A percutaneous release was performed with a 19-gauge hypodermic needle under local anaesthesia in the outpatient setting. All patients were evaluated with respect to clinical resolution of symptoms and general satisfaction. We report a 97% successful release and only one case of incomplete release. A result in terms of abolishing triggering was immediate and patient acceptance was excellent. By two weeks, all the patients had no pain at the operative site. After a mean follow-up of 30.2 months (range12-50), there had been no recurrences. There were no digital nerve injuries, flexor tendon injuries, and infections. The percutaneous release is a safe and effective technique, which provides significant cost savings. The time from onset of symptoms and grading prognostically is significant and affects the treatment outcome. We recommend the percutaneous technique for typical cases of trigger finger with a palpable nodule and reproducible mechanical triggering. This technique can be the treatment of choice for the established trigger finger (grade III and IV) with symptoms of more than few months' duration. The open technique is reserved for complicated cases such as florid tenosynovitis, locked digit, failed percutaneous release or those involving the thumb


Bone & Joint 360
Vol. 12, Issue 2 | Pages 24 - 28
1 Apr 2023

The April 2023 Wrist & Hand Roundup360 looks at: MRI-based classification for acute scaphoid injuries: the OxSMART; Deep learning for detection of scaphoid fractures?; Ulnar shortening osteotomy in adolescents; Cost-utility analysis of thumb carpometacarpal resection arthroplasty; Arthritis of the wrist following scaphoid fracture nonunion; Extensor hood injuries in elite boxers; Risk factors for reoperation after flexor tendon repair; Nonoperative versus operative treatment for displaced finger metacarpal shaft fractures.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_1 | Pages 87 - 87
1 Jan 2013
Ibrahim M Khan M Rostom M Platt A
Full Access

Introduction/Aim. Flexor tendon injuries of the hand are common with an incidence of over 3000 per annum in the UK. These injuries can affect hand function significantly. Early treatment with optimal repair is crucial to prevent disability. This study aimed at investigating the re-rupture rate following primary flexor tendon repair at our institution and to identify potential risk factors for re-rupture. Methods. 100 flexor tendons' injuries that underwent primary repair over a one-year period were reviewed retrospectively. Data was collected on age, gender, occupation, co morbidities, injured fingers, hand dominance, smoking status, zone of injury, time to surgery, surgeon grade, type of repair and suture, and antibiotic use on included patients. Causes of re-rupture were examined. We compared primary tendon repairs that had a re-rupture to those that did not re-rupture. Univariate and multivariate analysis was undertaken to identify the most significant risk factors for re-rupture. Results. 11 out of 100 (11%) repaired tendons went on to re-rupture. A significantly higher proportion of tendons re-rupture was noted when the repair was performed on the dominant hand (p-value = 0.009), in Zone 2 (0.001), and when a surgical delay of more than 72 hours from the time of injury occurred (0.01). Multivariate regression analysis identified repairs in Zone 2 to be the most significant predictor of re-rupture. Causes of re-rupture included infection in 5, rupture during rehabilitation exercises in 5 and fall in 1 patient. Conclusions. A re-rupture rate of 11% was noted in our study. Patients with Zone 2 injuries, repair on dominant hand and those with a surgical delay of more than 3 days were at higher risk of re-rupture. Careful consideration of these factors especially zone 2 injuries is crucial to reduce this rate. Providing a fast-track pathway for managing these patients can reduce time to surgery


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_1 | Pages 81 - 81
1 Jan 2013
Evans J Giddins G Miles T
Full Access

Aim. The purpose of this study was to develop and test the utility of a hybrid barbed-suture in the core repair of digital flexor tendon injuries. Despite offering advantages over traditional suture methods, concerns over the cost, strength to failure and biocompatibility of barbed sutures have hindered their development. Moreover the recent designs have been very complex. We have attempted to develop and test a simple barbed suture, to assess it's viability in flexor tendon repair and in particular to establish a baseline for the efficacy and modes of failure barbed sutures, in order to help provide a basis for future research. Method. The barbed suture device was constructed by inserting 3 steel barbs into the weaved construct of a braided polyester suture. The barbed sutures were inserted into 28 porcine lateral extensor tendons yielding a single sided core repair. Tensile testing of the repair was undertaken using a tabletop load frame with the distal end of the tendon fixed in a cryo clamp. Linear load testing to failure was undertaken. Maximum load, repair excursion and repair stiffness were recorded. Results. The barbed suture technique demonstrated a maximum load to failure of 40.4±16.4N. The excursion of the repair at failure point was 31.4±11.6mm. The stiffness of the repair derived from the linear elastic portion of the load displacement curve was 1.0±0.6N/mm. Conclusions. Use of this barbed suture construct offers a fast, easily applied method of flexor tendon repair. The maximum load to failure is comparable to the commonly used non-barbed suture methods. The suture excursion and stiffness findings suggest gap formation at low loads. Failure of the barbed suture seemed to be resisted by the collagen links between longitudinal tendon fibres. Further developments of this very modifiable construct may lead to a viable alternative to the current repair techniques


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_II | Pages 243 - 243
1 May 2009
Bois A Johnston G Classen D
Full Access

Spontaneous flexor tendon ruptures of the hand are uncommon and the current understanding of these ruptures is incomplete. The purpose of this study is to report five cases of spontaneous flexor tendon rupture in the hand, and to contrast the findings to those in the literature. A retrospective review of patients with flexor tendon injuries referred to our hand surgeons identified five patients who sustained a spontaneous rupture of the flexor digitorum profundus tendon. A literature search found a total of nineteen articles describing spontaneous tendon ruptures that met our criteria. We report five cases of spontaneous rupture involving the flexor digitorum profundus tendon. One case involves an abnormal intertendinous connection between the ring and small finger profundus tendons and another involves a lumbrical muscle variant. To our knowledge, the latter has not been reported in association with spontaneous tendon rupture. In reviewing the literature for spontaneous flexor tendon ruptures, a total of fifty spontaneous ruptures in forty-three cases was found. The majority involve the profundus tendon of the small finger in the palm. The ruptures most often occur during periods of peak strain, but can also occur without identifiable trauma. This study provides a detailed overview of spontaneous flexor tendon ruptures in the hand not found in the literature. The pathogenesis of spontaneous tendon ruptures is still unclear and is likely multifactorial. Although spontaneous flexor tendon ruptures of the hand are uncommon, these ruptures occur more often than one might recognise


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_III | Pages 470 - 471
1 Sep 2009
Mehdinasab S Sarrafan N Tabatabei S
Full Access

Extensor tondon lacerations are much more common than flexor tendon injuries. The outcome of this lesions depends on mamy factors including severity of initial trauma, coexisting lesions, of the hand, site of the laceration, experience of the surgeon, and post operative rehabilitation. The aim of this prospective study was to review our results of primary extensor tendon repair with regard to the zone of injury. During a period of 28 months, 32 patients with open extensor tendon laccerations were repaired by modified kessler technique using 4-0 nonabsorbable suture. After tendon repair, immobilization with a volar splint was applied for 4-weeks and physiotherapy was carried out. Patients were followed–up for a mean of 12 months. we used the 5 extensor tendon zones and results were assesed using Miller’s rating system. Patents with closed tendon ruptures or concomitant hand fracture were excluded from the study. Seventy two extensor tendons were repaired. The mean age of patients was 24.6 years (17–46 y). Excellent and good resalts were obtained as the follows: in zone 5(88/4%), zone 3 (84%), zone 2(55.5%), zone 4(42.7%), zone 1(40%). Results were poor in zone 4(42.8%), zone 1(40%), zone 2(22.2%), zone 3(4%), and zone 5(3.9%). No in fection was seen. We found a strong correlation between the site of the repair and outcome. More excellent and good results were obtained when the repair was performed distal to the extensor retinaculum (Zone 3), and above the wrist (Zone 5). Unsatisfactory results were seen when the tendon repair was done at or near DIP joint (zone 1), in the region of complex extensor mechanism (zone 2) or beneth the extensor retinaculum (zone 4). We cocluded the anatomic location of tendon repair has an important effect in outcome


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_III | Pages 411 - 411
1 Oct 2006
Talwalkar S Evans C Trail I McGrouther D
Full Access

Objective: To determine if the anatomical location of a tendon (hand or forearm) influences fibroblast function in the presence of physical forces. Introduction Tendons are anatomical structures specialized to transmit high tensile loads from muscle to bone. When damaged, clinical recovery is slow and incomplete. Various authors have shown that application of tensile loading during recovery (such as in early active motion following hand flexor tendon repair) will accelerate the recovery of tensile strength. The mechanism is unknown and the optimum loading regime has not been quantitated. It is likely that similar influences are working in rheumatoid arthritis but there is clinical evidence that the response to applied load is very different. In this study a commercial system (Bio stretch) was used to apply different strain regimes to cells in culture, and then to assess the response by a series of quantitative methodologies. Materials Cells were obtained by the explant technique from tendons of the hand and forearm to generate confluent cultures. In this experiment fibroblasts cultured from intra-synovial tendons (Group 1)were compared with cultured fibroblasts of forearm tendons (Group II). We used the Biostretch Apparatus (ICCT Technologies Canada), to stretch fibroblasts in a gel foam (Helistat, Integra TM ) construct. The Biostretch apparatus uses a magnetic field to stretch cells within the gel foam. After seeding the gel foam pieces (1cm2) with a concentrated cell suspension (4 x105 cells/100 μlitre) , the apparatus was used at 40% stretch, with a burst time of 15 minutes and a rest time of 45 minutes at 37° C and 60 cycles a second for 24 hours. The experiment was performed in triplicate for both type of cells (Group I & II), with another group of cells serving as controls. At the end of 24 hours the BCA method was used to estimate Total Protein content while the Sircol method was used to determine Type 1 Collagen levels. Results: Preliminary results indicate that there is a trend towards increased secretion of proteins and collagen in the stretched samples compared to the controls. Similarly the fibroblasts obtained from intra-synovial tendons seemed to produce more total protein and collagen as compared to the forearm. However both these observations failed to reach statistical significance. Conclusions: Previous work (. Evans CE et al. 2001. ) has shown no difference between collagen and protein production between flexor and extensor tendon, even under strain,. In this study the increased production of matrix proteins and collagen under the influence of physical strain may explain why flexor tendon injuries in the hand tend to heal with the formation of adhesions and poor functional results as compared with the forearm where the results tend to be uniformly better. However it must be stressed that these are preliminary results and further work will be required to provide definitive data


Bone & Joint 360
Vol. 11, Issue 2 | Pages 27 - 30
1 Apr 2022


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_II | Pages 170 - 170
1 Feb 2004
Ditsios K Burns M Boyer M Gelberman R Silva M
Full Access

Introduction: Recent in vivo studies of flexor tendon midsubstance healing have indicated that during the first 10 days after injury and repair there is no increase in ultimate tensile force. In contrast, there is an increase of approximately 170% in the rigidity (stiffness) of the repair site and a decrease of more than 45% in the repair-site strain at 20 N force. The basis for the increase in rigidity during the early stages of tendon healing is not known, but may be due to either biological or mechanical factors. In particular, cyclic loading of the tendon repair site during post-operative rehabilitation may have a mechanical conditioning effect that increases the stiffness of the repair site independent of repair-site healing. Our objective was to determine whether or not cyclic loading of repaired flexor tendons causes an in increase in repair-site rigidity and whether or not this increase depends on the level of applied force. We simulated 10 days of passive motion rehabilitation by applying 6000 loading cycles to repaired flexor tendons ex vivo at force levels generated during passive motion rehabilitation. We then evaluated the tensile mechanical properties. We hypothesized that cyclic loading causes an increase in repair-site rigidity and a decrease in repair-site strain. Materials and Methods Forty-eight flexor digitorum profundus (FDP) tendons with attached distal phalanges were obtained from twelve hindlimbs of six adult mongrel dogs. Specimens were randomly assigned to one of three groups: control (no loading), low-force (5 N) cyclic loading or high force (17 N) cyclic loading. Tendons were transected in Zone II, 4 cm proximal to the insertion site. They were repaired using a four-strand modified Kessler technique with double-stranded 4-0 Supramid suture (S. Jackson) supplemented with a running peripheral suture of 6-0 Prolene (Ethicon). For cyclic loading, the distal phalanx and proximal tendon stump were placed in custom clamps attached to a materials testing machine (Instron 8500R). Tendons in the low-force and high-force groups were loaded for 6000 cycles at 2 Hz from 0.5 N to peak forces of 5 and 17 N, respectively. The force levels were chosen to match the peak tendon forces that were measured in vivo for low- and high-force passive motion rehabilitation protocols of the canine forelimb; 6000 cycles were used to simulate the number of cycles applied during a 10-day period of rehabilitation (600 cycles/day). Specimens in the control group were sham loaded for an equivalent period of time (50 minutes). After cyclic loading, specimens were allowed to recover for 1 hour and then tested to failure in tension. From plots of force versus repair-site strain we determined ultimate (maximum) force (N), repair-site rigidity (N/[mm/mm]) and repair-site strain (%) at 20 N force. One-way analysis of variance was used to determine the effect of loading on tensile properties. Results: Specimens subjected to high-force cyclic loading had significantly increased rigidity compared to specimens in the low-force and control groups. Rigidity in the high-force group was increased by 100% compared to control. Similarly, repair-site strain at 20 N was decreased by 50% in the high-force group compared to control group. Ultimate force was increased in the high force group compared to control (p = 0.02; Table), but the magnitude of the increase was only 13%. There were no significant differences between the low-force and control groups (p > 0.05). Discussion: Based on our findings, we conclude: 1) Repair-site rigidity is increased by 100% and repair-site strain decreased by 50% following 6000 cycles of high-force (17 N) loading. In contrast, ultimate force is changed only slightly (13%) by high-force loading. 2) Mechanical conditioning of the repair site by repetitive forces applied during rehabilitation may have a consequence that has not been noted previously, i.e. it leads to increases in rigidity and decreases in strain. This effect may explain in part the changes in tensile properties observed after only 10 days of healing in vivo. 3) The lack of effect of low-force (5 N) loading on repair-site rigidity and strain is in contrast to the previous in vivo findings in which rigidity increased in the low-force rehabilitation group. This discrepancy suggests that the observed in vivo changes can not be explained entirely by mechanical conditioning effects. 4) Therefore, both biological and mechanical factors are likely to play an important role in the rapid changes in repair-site mechanical properties that occur following flexor tendon injury and repair


Bone & Joint 360
Vol. 9, Issue 4 | Pages 26 - 30
1 Aug 2020


Bone & Joint 360
Vol. 7, Issue 4 | Pages 19 - 22
1 Aug 2018


Bone & Joint Research
Vol. 6, Issue 3 | Pages 179 - 185
1 Mar 2017
Wu JH Thoreson AR Gingery A An KN Moran SL Amadio PC Zhao C

Objectives

The present study describes a novel technique for revitalising allogenic intrasynovial tendons by combining cell-based therapy and mechanical stimulation in an ex vivo canine model.

Methods

Specifically, canine flexor digitorum profundus tendons were used for this study and were divided into the following groups: (1) untreated, unprocessed normal tendon; (2) decellularised tendon; (3) bone marrow stromal cell (BMSC)-seeded tendon; and (4) BMSC-seeded and cyclically stretched tendon. Lateral slits were introduced on the tendon to facilitate cell seeding. Tendons from all four study groups were distracted by a servohydraulic testing machine. Tensile force and displacement data were continuously recorded at a sample rate of 20 Hz until 200 Newton of force was reached. Before testing, the cross-sectional dimensions of each tendon were measured with a digital caliper. Young’s modulus was calculated from the slope of the linear region of the stress-strain curve. The BMSCs were labeled for histological and cell viability evaluation on the decellularized tendon scaffold under a confocal microscope. Gene expression levels of selected extracellular matrix tendon growth factor genes were measured. Results were reported as mean ± SD and data was analyzed with one-way ANOVAs followed by Tukey’s post hoc multiple-comparison test.


Bone & Joint Research
Vol. 7, Issue 3 | Pages 213 - 222
1 Mar 2018
Tang X Teng S Petri M Krettek C Liu C Jagodzinski M

Objectives

The aims of this study were to determine whether the administration of anti-inflammatory and antifibrotic agents affect the proliferation, viability, and expression of markers involved in the fibrotic development of the fibroblasts obtained from arthrofibrotic tissue in vitro, and to evaluate the effect of the agents on arthrofibrosis prevention in vivo.

Methods

Dexamethasone, diclofenac, and decorin, in different concentrations, were employed to treat fibroblasts from arthrofibrotic tissue (AFib). Cell proliferation was measured by DNA quantitation, and viability was analyzed by Live/Dead staining. The levels of procollagen type I N-terminal propeptide (PINP) and procollagen type III N-terminal propeptide (PIIINP) were evaluated with enzyme-linked immunosorbent assay (ELISA) kits. In addition, the expressions of fibrotic markers were detected by real-time polymerase chain reaction (PCR). Fibroblasts isolated from healthy tissue (Fib) served as control. Further, a rabbit model of joint contracture was used to evaluate the antifibrotic effect of the three different agents.


Bone & Joint 360
Vol. 5, Issue 2 | Pages 18 - 21
1 Apr 2016