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Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_18 | Pages 32 - 32
14 Nov 2024
Mungalpara N Kim S Baker H Lee C Shakya A Chen K Athiviraham A Koh J Elhassan B Maassen NH Amirouche F
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Introduction

Supraspinatus and infraspinatus tears (Massive Rotator Cuff Tear- MRCT) cause compensatory activation of the teres minor (TM) and subscapularis (SubS) to maintain humeral head alignment. This study measures force changes in TM and SubS using a dynamic shoulder testing setup. We hypothesize that combining superior capsule reconstruction (SCR) and lower trapezius tendon (LTT) transfer will correct rotator cuff forces.

Methods

Eight fresh-frozen human shoulder specimens from donors aged 55-75 (mean = 63.75 years), balanced for gender, averaging 219.5 lbs, were used. Rotator cuff and deltoid tendons were connected to force sensors through a pulley system, with the deltoid linked to a servohydraulic motor for dynamic force measurement. The system allowed unrestricted humeral abduction from 0 to 90 degrees.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_18 | Pages 125 - 125
14 Nov 2024
Mungalpara N Kim S Baker H Lee C Shakya A Chen K Athiviraham A Koh J Elhassan B Maassen NH Amirouche F
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Introduction

Treatment strategies for irreparable Massive Rotator Cuff Tears (MRCTs) are debatable, especially for younger, active patients. Superior Capsular Reconstruction (SCR) acts as a static stabilizer, while Lower Trapezius Transfer (LTT) serves as a dynamic stabilizer. This study compares the biomechanical effectiveness of SCR and LTT, hypothesizing that their combination will enhance shoulder kinematics.

Methods

Eight human shoulders from donors aged 55-75 (mean = 63.75 years), balanced for gender, averaging 219.5 lbs, were used. Rotator cuff and deltoid tendons were connected to force sensors through a pulley system, with the deltoid linked to a servohydraulic motor for dynamic force measurement.


Bone & Joint Research
Vol. 13, Issue 4 | Pages 157 - 168
4 Apr 2024
Lin M Chen G Yu H Hsu P Lee C Cheng C Wu S Pan B Su B

Aims

Osteosarcoma is the most common primary bone malignancy among children and adolescents. We investigated whether benzamil, an amiloride analogue and sodium-calcium exchange blocker, may exhibit therapeutic potential for osteosarcoma in vitro.

Methods

MG63 and U2OS cells were treated with benzamil for 24 hours. Cell viability was evaluated with the MTS/PMS assay, colony formation assay, and flow cytometry (forward/side scatter). Chromosome condensation, the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay, cleavage of poly-ADP ribose polymerase (PARP) and caspase-7, and FITC annexin V/PI double staining were monitored as indicators of apoptosis. Intracellular calcium was detected by flow cytometry with Fluo-4 AM. The phosphorylation and activation of focal adhesion kinase (FAK) and signal transducer and activator of transcription 3 (STAT3) were measured by western blot. The expression levels of X-linked inhibitor of apoptosis protein (XIAP), B-cell lymphoma 2 (Bcl-2), B-cell lymphoma-extra large (Bcl-xL), SOD1, and SOD2 were also assessed by western blot. Mitochondrial status was assessed with tetramethylrhodamine, ethyl ester (TMRE), and intracellular adenosine triphosphate (ATP) was measured with BioTracker ATP-Red Live Cell Dye. Total cellular integrin levels were evaluated by western blot, and the expression of cell surface integrins was assessed using fluorescent-labelled antibodies and flow cytometry.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_7 | Pages 11 - 11
4 Apr 2023
O’Beirne A Pletikosa Z Cullen J Bassonga E Lee C Zheng M
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Nerve transfer is an emerging treatment to restore upper limb function in people with tetraplegia. The objective of this study is to examine if a flexible collage sheet (FCS) can act as epineurial-like substitute to promote nerve repair in nerve transfer.

A preclinical study using FCS was conducted in a rat model of sciatic nerve transection. A prospective case series study of nerve transfer was conducted in patients with C5-C8 tetraplegia who received nerve transfer to restore upper limb function. Motor function in the upper limb was assessed pre-treatment, and at 6-,12-, and 24-months post-treatment.

Macroscopic assessment in preclinical model showed nerve healing by FCS without encapsulation or adhesions. Microscopic examination revealed that a new, vascularised epineurium-like layer was observed at the FCS treatment sites, with no evidence of inflammatory reaction or nerve compression. Treatment with FCS resulted in well-organised nerve fibres with dense neurofilaments distal to the coaptation site. Axon counts performed proximal and distal to the coaptation site showed that 97% of proximal axon count of myelinated axons regenerated across the coaptation site after treatment with CND. In the proof of concept clinical study 17 nerve transfers were performed in five patients. Nerve transfers included procedures to restore triceps function (N=4), wrist/finger/thumb extension (N=6) and finger flexion (N=7). Functional motor recovery (MRC ≥3) was achieved in 76% and 88% of transfers at 12 and 24 months, respectively.

The preclinical study showed that FCS mimics epineurium and enable to repair nerve resembled to normal nerve tissue. Clinical study showed that patients received nerve transfer with FCS experienced consistent and early return of motor function in target muscles. These results provide proof of concept evidence that CND functions as an epineurial substitute and is promising for use in nerve transfer surgery.


The Bone & Joint Journal
Vol. 104-B, Issue 7 | Pages 902 - 908
1 Jul 2022
Hsu P Lee C Lin S Kuo KN Wu K Wang T

Aims

The aim of this study was to compare outcomes of guided growth and varus osteotomy in treating Kalamchi type II avascular necrosis (AVN) after open reduction and Pemberton acetabuloplasty for developmental dysplasia of the hip (DDH).

Methods

This retrospective study reviewed patients undergoing guided growth or varus osteotomy for Kalamchi type II AVN between September 2009 and January 2019. All children who had undergone open reduction and Pemberton acetabuloplasty for DDH with a minimum two-year follow-up were enrolled in the study. Demographic and radiological data, which included the head-shaft angle (HSA), neck-shaft angle (NSA), articulotrochanteric distance (ATD), Sharp angle (SA), and lateral centre-edge angle (LCEA) at baseline, two years, and at the extended follow-up, were compared. Revision rates were evaluated. Clinical outcomes using the Harris Hip Score were assessed two years postoperatively.


Bone & Joint Open
Vol. 3, Issue 5 | Pages 348 - 358
1 May 2022
Stokes S Drozda M Lee C

This review provides a concise outline of the advances made in the care of patients and to the quality of life after a traumatic spinal cord injury (SCI) over the last century. Despite these improvements reversal of the neurological injury is not yet possible. Instead, current treatment is limited to providing symptomatic relief, avoiding secondary insults and preventing additional sequelae. However, with an ever-advancing technology and deeper understanding of the damaged spinal cord, this appears increasingly conceivable. A brief synopsis of the most prominent challenges facing both clinicians and research scientists in developing functional treatments for a progressively complex injury are presented. Moreover, the multiple mechanisms by which damage propagates many months after the original injury requires a multifaceted approach to ameliorate the human spinal cord. We discuss potential methods to protect the spinal cord from damage, and to manipulate the inherent inhibition of the spinal cord to regeneration and repair. Although acute and chronic SCI share common final pathways resulting in cell death and neurological deficits, the underlying putative mechanisms of chronic SCI and the treatments are not covered in this review.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_11 | Pages 29 - 29
1 Sep 2021
Lee C Lee MG Lim WJ Liu Y Pakdeenit B Kim JS
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Although interlaminar endoscopic lumbar discectomy (IELD) is considered to be less invasive than microscopic lumbar discectomy (MLD) in treatment of lumbar herniated nucleus pulposus, the radiologic change of multifidus muscles by each surgery has rarely been reported. The aim of the present study was to compare the quantitative and qualitative changes of multifidus muscles between two surgical approaches and to analyze the correlation between various parameters of multifidus muscles and long term surgical outcome.

21 patients who received MLD and 18 patients who received IELD in a single tertiary hospital were enrolled and their preoperative, postoperative (≤15 days), and follow-up (≥6 months) MRIs were analyzed. The cross-sectional area (CSA) and fatty degeneration rate (FD) were quantitatively estimated at the level of surgery. The correlations among CSA, FD, body mass index, follow-up visual analogue scale(VAS) and Oswestry Disability Index(ODI) were assessed.

Mean intervals of postoperative MRI and follow-up MRI from surgery were 3.0±3.7 days and 14.5±10.7 months, respectively. During the follow-up period, VAS was improved from 7.1±1.3 to 2.1±1.8 in MLD and from 8.2±1.4 to 2.2±1.8 in IELD. In cases of MLD, comparing with preoperative MRI, ipsilateral CSA was significantly increased in postoperative MRI (795.6mm2 vs. 906.5mm2, p<0.01), but it was not significantly different in follow-up MRI (795.6mm2 vs. 814.4mm2, p=1.00). However, in case of IELD, the ipsilateral CSAs in preoperative, postoperative, and follow-up periods were 892.0 mm2, 909.3 mm2, and 900.3 mm2, respectively. These changes were not significant over time (p=0.691). The ipsilateral FDs were not significantly changed between preoperative and follow-up periods in both MLD (21.4% vs. 20.9%, p=0.81) and IELD groups (23.5% vs. 21.8%, p=0.19). The increment of ipsilateral CSA had significant correlations with follow-up ODI (r=−0.368, p=0.02).

Comparing with IELD, MLD induced more surgical trauma on multifidus muscle in postoperative period, but the muscular damage was recovered in follow-up period. IELD can minimize surgical trauma on multifidus muscle showing similar pain relief as MLD. Favorable surgical outcome in follow-up period may be related to increment of multifidus muscle volume.

Figure 1

(A-C) The multifidus muscles in preoperative, postoperative, and follow-up periods, respectively, in patient with MLD. Comparing with preoperative period, the CSA of right multifidus muscle (ipsilateral side) was increased in postoperative period, but recovered in follow-up period. (D-F) The multifidus muscle in preoperative, postoperative, and follow-up periods, respectively, in patient with IELD. The CSA of left multifidus muscles (ipsilateral side) was not significantly changed over time. Comparing preoperative MRIs with follow-up MRIs, the FDs of multifidus muscles were not significantly changed regardless of surgical technique.

Figure 2

The CSA was measured by marking region of interest (ROI) and FD was measured by calculating the rate of pixels beyond the threshold in ROI. All measurements were performed using ImageJ software (version 1.52a, National Institutes of Health, Bethesda, Maryland, USA).

For any figures or tables, please contact the authors directly.


The Bone & Joint Journal
Vol. 102-B, Issue 9 | Pages 1242 - 1247
3 Sep 2020
Hsu P Wu K Lee C Lin S Kuo KN Wang T

Aims

Guided growth has been used to treat coxa valga for cerebral palsy (CP) children. However, there has been no study on the optimal position of screw application. In this paper we have investigated the influence of screw position on the outcomes of guided growth.

Methods

We retrospectively analyzed 61 hips in 32 CP children who underwent proximal femoral hemi epiphysiodesis between July 2012 and September 2017. The hips were divided into two groups according to the transphyseal position of the screw in the coronal plane: across medial quarter (Group 1) or middle quarter (Group 2) of the medial half of the physis. We compared pre- and postoperative radiographs in head-shaft angle (HSA), Reimer’s migration percentage (MP), acetabular index (AI), and femoral anteversion angle (FAVA), as well as incidences of the physis growing-off the screw within two years. Linear and Cox regression analysis were conducted to identify factors related to HSA correction and risk of the physis growing-off the screw.


Aims

The aim of this study was to compare patient-reported outcome measures (PROMs) and the Single Assessment Numerical Evaluation (SANE) score in patients treated with a volar locking plate for a distal radial fracture.

Methods

This study was a retrospective review of a prospective database of 155 patients who underwent internal fixation with a volar locking plate for a distal radial fracture between August 2014 and April 2017. Data which were collected included postoperative PROMs (Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH) and Patient-Rated Wrist Evaluation (PRWE)), and SANE scores at one month (n = 153), two months (n = 155), three months (n = 144), six months (n = 128), and one year (n = 73) after operation. Patients with incomplete data were excluded from this study. Correlation and agreement between PROMs and SANE scores were evaluated. Subgroup analyses were carried out to identify correlations according to variables such as age, the length of follow-up, and subcategories of the PRWE score.


The Bone & Joint Journal
Vol. 101-B, Issue 10 | Pages 1379 - 1384
1 Oct 2019
Park J Park S Lee C

Aims

This study aimed to evaluate the incidence and prognosis of patients with spinal metastasis as the initial manifestation of malignancy (SM-IMM).

Patients and Methods

We retrospectively reviewed the electronic medical records of 338 patients who underwent surgical treatment for metastatic spinal disease. The enrolled patients were divided into two groups. The SM-IMM group included patients with no history of malignancy whose site of primary malignancy was diagnosed after the identification of spinal metastasis. The other group included patients with a history of treatment for primary malignancy who then developed spinal metastasis (SM-DTM). The incidence of SM-IMM by site of primary malignancy was calculated. The difference between prognoses after surgical treatment for SM-IMM and SM-DTM was established.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_9 | Pages 46 - 46
1 May 2017
Page P Lee C Rogers B
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Background

Fractures of the femoral neck occurring outside the capsule of the hip joint are assumed to have an intact blood supply and hence their conventional management is by fixation rather than arthroplasty. The dynamic hip screw and its variants have been used over many years to fix such fractures but have inherent vulnerabilities; they require an intact lateral femoral cortex, confer a relatively long moment arm to the redistribution of body weight and may cause a stress riser due to the plate with which they are fixed to the femur. Intramedullary devices for fixation of proximal femoral fractures have a shorter moment arm, can be distally locked with reduced perforation of the femoral cortex and are believed to be inherently more stable. For these reasons, a number of surgeons believe them to be superior to the DHS for all extracapsular fractures and their use is now widespread. In this study, we present the usage trends of both devices in extracapsular fractures over the last five years and set these results in the context of patient demographics.

Methods

Our departmental electronic patient management system was used to identify all patients undergoing surgery coded as either DHS or its variants or intramedullary fixation of hip fracture. The patients’ age, sex and American Society of Anaesthesiologists grading were recorded. Comparison between groups was made using appropriate tests in SPSS.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_5 | Pages 34 - 34
1 Mar 2017
Mueller U Lee C Thomsen M Heisel C Kretzer J
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Introduction

This study was performed to investigate the failure mechanism of one specific hip arthroplasty cup design that has shown a high clinical failure rate. The aim of this study was to identify general design problems of this polyethylene inlay.

Material and Methods

55 consecutive retrievals of a cementless screw ring (Mecron) were collected. In any case a 32 mm ceramic head was used. All implants failed due to aseptic loosening. The follow-up of the implants was 3 to 16 years. We recorded backside wear, fatigue of the polyethylene at the flanges on the outer rim and at the cup opening (32 mm inner diameter). To assess the deformation of the inlay, the smallest and the median diameter of the cup opening were measured using a 3 dimensional coordinate measuring machine (Multisensor, Mahr, Germany).


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_4 | Pages 115 - 115
1 Feb 2017
Chun Y Cho Y Lee C Bae C Rhyu K
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Purpose

This study was performed to evaluate clinical and radiographic outcomes of Hip Resurfacing Arthroplasty for treatment of haemophilic hip arthropathy.

Material & Method

Between 2002 and 2013, 17 cases of hip resurfacing arthroplasties were performed in 16 haemophilic patients (13 cases of haemophilia A, 2 cases of haemophilia B, 2 cases of von Willebrand disease). The average age of the patients was 32.5(range: 18∼52) years. The average follow up period from the operation was 6.3 (range: 2∼13) years. In this study, the subjects that completed follow-up were composed of 5 cases composed of patients who were treated with Conserve plus® hip resurfacing system, 5 cases composed of patients who were treated with Durom® hip resurfacing system, 4 cases who were treated with ASR® hip resurfacing system, and 3 cases who were treated with Birmingham® hip resurfacing system. The Modified Harris hip score, the range of motion of the hip joint, perioperative coagulation factor requirements and complications associated with bleeding were evaluated as part of the clinical assessment. For the radiographic assessment, fixation of component, presence of femoral neck fracture, osteolysis, loosening and other complications were evaluated.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_10 | Pages 143 - 143
1 May 2016
Yoon S Lee C Hur J Kwon O Lee H
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Introduction

Mechanically aligned total knee arthroplasty(TKA) relies on restoring the hip-knee-ankle angle of the limb to neutral or as close to a straight line as possible. This principle is based on studies that suggest limb and knee alignment is related long term survival and wear. For that cause, there has been recent attention concerning computer-assisted TKA and robot is also one of the most helpful instruments for restoring neutral alignment as known. But many reported data have shown that 20% to 25% of patients with mechanically aligned TKA are dissatisfied. Accordingly, kinematically aligned TKA was implemented as an alternative alignment strategy with the goal of reducing prevalence of unexplained pain, stiffness, and instability and improving the rate of recovery, kinematics, and contact forces. So, we want to report our extremely early experience of robot-assisted TKA planned by kinematic method.

Materials and Methods

This study evaluated the very short term results (6 weeks follow up) after robot-assisted TKA aligned kinematically. 50 knees in 36 patients, who could be followed up more than 6 weeks after surgery from December 2014 to January 2015, were evaluated prospectively. The diagnosis was primary osteoarthritis in all cases. The operation was performed with ROBODOC (ISS Inc., CA, USA) along with the ORTHODOC (ISS Inc., CA, USA) planning computer. The cutting plan was made by single radius femoral component concept, each femoral condyles shape-matched method along the transverse axis using multi-channel CT and MRI to place the implant along the patient's premorbid joint line. Radiographic measurements were made from long bone scanograms. Clinical outcomes and motion were measured preoperatively and 6 weeks postoperatively.


We compared the ceiling effects of two patient-rating scores, the Disability of the Arm, Shoulder and Hand (DASH) and Patient-Rated Wrist Evaluation (PRWE), and a physician-rating score, the Modified Mayo Wrist Score (MMWS) in assessing the outcome of surgical treatment of an unstable distal radial fracture. A total of 77 women with a mean age of 64.2 years (50 to 88) who underwent fixation using a volar locking plate for an unstable distal radial fracture between 2011 and 2013 were enrolled in this study. All completed the DASH and PRWE questionnaires one year post-operatively and were assessed using the MMWS by the senior author. The ceiling effects in the outcome data assessed for each score were estimated.

The data assessed with both patient-rating scores, the DASH and PRWE, showed substantial ceiling effects, whereas the data assessed with MMWS showed no ceiling effect.

Researchers should be aware of a possible ceiling effect in the assessment of the outcome of the surgical treatment of distal radial fractures using patient-rating scores. It could also increase the likelihood of a type II error.

Cite this article: Bone Joint J 2015;97-B:1651–6.


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_8 | Pages 10 - 10
1 Jun 2015
Lee C King C Freeman R Edmondson M Guthrie H
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The “Golden Patient” is suitability worked up to be the first theatre case of the day; the aim being to improve theatre efficiency. A previous audit of theatre activity demonstrated that the average knife to skin time being achieved across 3 daily trauma lists was 10.12. Over 2-months we introduced a Golden Patient Pathway and completed the audit cycle. The pathway involved a checklist to ensure the completion of essential clinical tasks for each designated golden patient. Activities from 74 trauma theatre cases were reviewed. 47 golden patients remained first whilst 27 were deferred for reasons including non-suitability for golden patient status and emergent cases given clinical priority. The average theatre call time was 24 minutes earlier and the average knife-to-skin time was 15 minutes earlier than non-golden patients during the re-audit. However, when compared to the initial audit the knife-to-skin time had only improved by 3 minutes. Reasons effecting theatre efficiency are multifactorial and other organisational changes had occurred between the audits. This study demonstrates that while the Golden Patient Pathway can improve theatre start times it is not the whole solution. Communication, anaesthetic job plans, portering arrangements, equipment storage and theatre staffing also need to be reviewed.


The Bone & Joint Journal
Vol. 97-B, Issue 2 | Pages 229 - 234
1 Feb 2015
Choi W Lee HJ Kim D Lee C Lee BG Kim J Lee K

We performed a retrospective study to determine the effect of osteoporosis on the functional outcome of osteoporotic distal radial fractures treated with a volar locking plate. Between 2009 and 2012 a total of 90 postmenopausal women with an unstable fracture of the distal radius treated with a volar locking plate were studied. Changes in the radiological parameters of 51 patients with osteoporosis (group 1, mean age 66.9, mean T-score –3.16 (sd 0.56)) were not significantly different from those in 39 patients without osteoporosis (group 2, mean age 61.1, mean T-score –1.72 (sd 0.57)). The mean Disabilities of the Arm, Shoulder and Hand (DASH) score at final follow-up was 11.5 (sd 12.2) in group 1 and 10.5 (sd 13.25) in group 2. The mean modified Mayo wrist score at final follow-up was 79.0 (sd 14.04) in group 1 and 82.6 (sd 13.1) in group 2. However, this difference was not statistically significant (p = 0.35 for DASH score, p = 0.2 for modified Mayo wrist score). Univariable and multivariable logistic regression analysis showed that only the step-off of the radiocarpal joint was related to both a poor DASH and modified Mayo wrist score. Pearson’s correlation coefficient showed a weak negative relationship only between the T-score and the change in volar tilt (intraclass coefficient –0.26, p = 0.02).

We found that osteoporosis does not have a negative effect on the functional outcome and additional analysis did not show a correlation between T-score and outcome.

Cite this article: Bone Joint J 2015;97-B:229–34.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_17 | Pages 19 - 19
1 Nov 2014
Yousaf S Lee C Khan A Hossain N Edmondson M
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Introduction:

Early stabilization has the potential to expedite early return to function and reduce hospital stay thus reducing cost to health care. A clinical audit was performed to test the hypothesis that early surgical stabilization lowers the rate of soft tissue complications and is not influenced by choice of distal fibular implants used for stabilization of ankle fractures.

Methods:

All surgically treated adult patients with isolated unstable ankle fracture were included from April 2012 to April 2013 at a MTC in UK. Patients with poly-trauma were excluded.

All patients underwent a standard surgical protocol: aim for early definitive surgical fixation (ORIF) within 24 hours however if significantly swollen than temporary stabilization with an external fixation followed by a staged definitive fixation.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 367 - 367
1 Mar 2013
Yoon S Lee C Hur J Kwon O Trabish M Lee H Park J
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Introduction

The success of total knee arthroplasty depends on many factors, including the preoperative condition of the patient, the design and materials of the components and surgical techniques. It is important to position the femoral and tibial components accurately and to balance the soft tissues. Malpositioning of the component can lead to failures due to aseptic loosening, instability, polyethylene wear and dislocation of the patella. In order to improve post-operative alignment, computer-aid systems have been developed for total knee arthroplasty. Many clinical and experimental studies of these systems have shown that the accuracy of implanted components can be improved in spite of the increase in costs and operating time. This may not, however, improve the outcome in the short-term. Restoration of the normal mechanical axis of the knee and balancing of the surrounding soft tissues have been shown to have an important bearing on the final outcome of knee replacement operations. In severely deformed knees, whether varus or valgus, these goals may be difficult to achieve. We compared the radiologic results of the mechanical axis and implant position of Total Knee Arthroplasty using a robot-assisted method with conventional manually implanted method in severe varus deformed knee.

Materials and Methods

A data set of 50 consecutive cases that were performed from April 2007 to December 2010 using the robot assisted TKA(Group A) were compared with a data set of 50 consecutive cases from the same period that were done using conventional manual TKA(Group B). All cases had a preoperative mechanical varus deformity >15° and one brand of implant was used on all cases. The diagnosis was primary osteoarthritis in all knees. The operations were performed by one-senior author with the same robot system, ROBODOC (ISS Inc., CA, USA) along with the ORTHODOC (ISS Inc., CA, USA) planning computer. (See Figure 1.) The radiological evaluations included mechanical axis, implant position (α,β,γ,δ angle) according to the system of American Knee Society.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 335 - 335
1 Mar 2013
Song I Lee C
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Purpose

We analyzed the frequency, causes and treatment of dislocation of polyethylene insertion among various causes of failure of unicompartmental knee arthroplasty.

Materials and Methods

We studied 69 knee joints of 65 patients who underwent medial unicompartmental knee arthroplasty using from June 2005 to December 2010. Average age was 61.8 and average follow-up period was 20 months. Radiologic results evaluated preoperative and postopertative mechanical axis deviation, tibio-fibular angle and postoperative implant position in total 69 knees(A group), failed 15 cases(B group) and 10 cases(C group) of bearing dislocation. We demonstrated treatment on failure group and analyzed preoperative and postoperative HSS and Lysolm score.