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A comparison of discectomy and arthroscopic lysis and lavage for the treatment of chronic closed lock of the temporomandibular joint: A randomized outcome study
CLINICAL ARTICLES J Oral Maxillofac Surg 59:972-977, 2001
A Comparison of Discectomy and Arthroscopic Lysis and Lavage for the Treatment of Chronic Closed Lock of the Temporomandibular Joint: A Randomized Outcome Study Anders B. Holmlund, DDS, PhD,* Susanna Axelsson, DDS, PhD,† and Go ¨ ran W. Gynther, DDS, PhD‡ Purpose:
The study compared the efficacy of discectomy or arthroscopic lysis and lavage in patients with chronic closed lock of the temporomandibular joint (TMJ) in a prospective, randomized clinical trial. Patients and Methods: Twenty-two patients with a clinical diagnosis of chronic closed lock were prospectively randomized to either discectomy or arthroscopic lysis and lavage. The individual outcome in each patient was evaluated with a visual analog scale for pain and a questionnaire concerning mandibular functional impairment. The clinical evaluation included measurement of maximum interincisal opening and protrusion, recording of clicking and crepitation, and palpation for tenderness of the TMJ and jaw muscles. Recordings were made before the operation (baseline) and at the 1-year follow-up. Results: Twenty patients completed the study. Discectomy and arthroscopic lysis and lavage significantly reduced pain and improved mandibular function. Discectomy reduced pain somewhat more effectively than arthroscopic lysis and lavage. The clinical recordings at the 1-year follow-up indicated similarly good outcomes after both procedures. Conclusion: Both discectomy and arthroscopic lysis and lavage are effective surgical methods for treatment of chronic closed lock of the TMJ. Considering that arthroscopic lysis and lavage is a minimally invasive outpatient procedure, it should be used as the first choice in surgical treatment of this condition. © 2001 American Association of Oral and Maxillofacial Surgeons Chronic closed lock of the temporomandibular joint (TMJ) is a common indication for surgery of the TMJ.
Several methods have been proposed and evaluated. The oldest is discectomy, which was introduced in 1909 by Lanz.1 Although disregarded by some,2,3 it has survived for almost a century and is still widely used. It has also been thoroughly assessed in clinical trials. Prospective long-term studies in 3 centers have all shown a stable outcome and a low incidence of complications even after a long period.4-6 However, removal of the disc also has some deleterious effects, such as radiographic signs of osteoarthrosis,7 clinically reflected by an increased frequency of crepitation.5 Furthermore, some patients develop fibrous adhesions, which limit mandibular movement. Arthroscopy of the TMJ was first reported by Ohnishi in 1975.8 In 1986, Sanders described a simple method for lysis and lavage of the TMJ.9 It has been widely used, and several investigators have reported on its efficacy and noninvasiveness.10,11 However,
*Professor and Consultant, Department of Oral and Maxillofacial Surgery, Institution of Odontology, Karolinska Institutet/Huddinge University Hospital, Huddinge, Sweden. †Project Director, The Swedish Council on Technology Assessment in Health Care, Stockholm, Sweden. ‡Associate Professor and Consultant, Department of Oral and Maxillofacial Surgery, Institution of Odontology, Karolinska Institutet/Huddinge University Hospital, Huddinge, Sweden. Address correspondence and reprint requests to Dr Holmlund: Department of Oral and Maxillofacial Surgery, Institution of Odontology, Karolinska Institutet, Box 4064, S-141 04 Huddinge, Sweden; e-mail: [email protected] © 2001 American Association of Oral and Maxillofacial Surgeons
0278-2391/01/5909-0002$35.00/0 doi:10.1053/joms.2001.25818
972
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HOLMLUND, AXELSSON, AND GYNTHER
Table 1. DEMOGRAPHIC FINDINGS IN THE PATIENTS
Discectomy (n ⫽ 10) Arthroscopy (n ⫽ 10)
Age (yr)
Female/Male (No.)
Left/Right Joint (No.)
Mean Duration of Locking (mo)
37 (22–53) 32 (22–46)
10/0 8/2
5/5 6/4
8.5 (2–24) 20.5 (2–60)
very few outcome studies of discectomy and arthroscopic lysis and lavage fulfill the criteria for proper assessment.12 Thus, dropout of patients, specific inclusion and exclusion criteria, and methods for evaluation have not been adequately described, which limits the scientific value of such studies. Furthermore, the comparative analyses are rarely randomized. We have previously proposed that discectomy should be a standard procedure for comparisons in randomized trials.5 However, our experience in patients with chronic closed lock of the TMJ has indicated that arthroscopic lysis and lavage also can be useful.13 Thus, the goal of the present study was to compare the clinical outcome of the latter method with that of discectomy in a randomized prospective trial.
Patients and Methods Twenty-four patients fulfilled the following inclusion criteria: 1) clinical diagnosis of chronic closed lock of the TMJ (previous clicking in the TMJ replaced by pain in the TMJ and limitation of vertical and horizontal mandibular movements); 2) unilateral involvement; and 3) unsuccessful nonsurgical treatment for at least 3 months. Exclusion criteria included other TMJ disease, major jaw trauma, or a dentofacial deformity. Twenty-four consecutive patients fulfilling the inclusion criteria were asked if they would participate in the randomized study. Two patients declined to participate. The remaining 22 patients were randomized to either discectomy or arthroscopic lysis and lavage. However, 2 of these 22 patients were excluded at the time of the study. Both patients had been randomized for arthroscopic lysis and lavage. One patient recovered spontaneously before arthroscopy was performed, and 1 patient, in whom arthroscopy had been performed, developed polyarthritis related to a Borrelia infection 3 months after arthroscopy. The remaining 20 patients comprised the study material. Their demographic characteristics are shown in Table 1. All patients received full information about both procedures and our intention to evaluate the efficacy in a randomized fashion. They were asked to consider
the information provided and then to give their consent. They were then randomized to either discectomy or arthroscopic lysis and lavage using a randomization format. Discectomy was performed under general anesthesia, according to a previously described method.5 The joint was exposed through a preauricular incision. After excision of the disc, any irregularities on the condyle were smoothed with a diamond file. No autogenous or alloplastic replacement materials were inserted. The patients were admitted to the hospital the day before surgery and were discharged the day after surgery. Antibiotic coverage was given preoperatively (a single dose of clindamycin 600 mg intravenously). The procedure for arthroscopic lysis and lavage has also been described elsewhere.13 An inferolateral approach was used for trocar puncture, and an outflow needle was placed through the skin 5 mm anterior to and slightly below the entry of the trocar. The upper compartment of the TMJ was examined with a 30° telescope (Karl Storz GmbH & Co, Tuttlingen, Germany). Any fibrous adhesions were released in a semiblind fashion using a blunt trocar. The upper compartment was then irrigated with 100 mL isotonic saline solution, using the outflow needle for injection and the arthroscopic cannula for outflow. After arthroscopy, the patient remained in the clinic for about 1 hour to recover before being discharged. All arthroscopic procedures were performed in the outpatient clinic under local anesthesia and intravenous sedation with a short-acting benzodiazepine (midazolam). No antibiotic coverage or steroid injections were given. The surgical procedures were performed by 2 oral and maxillofacial surgeons (A.B.H. and G.W.G.), who worked in the same department and were carefully calibrated regarding the inclusion and exclusion criteria and the surgical technique. Pain in the TMJ on mandibular function (opening the mouth, chewing, biting, yawning) was recorded at baseline (the day before surgery) and at follow-up (3 months and 1 year) using a 10-cm visual analog scale (VAS). The scale was divided into 10 fields and, if pain was present, the patient was asked to select a field from 1 to 10. If there was no pain, it was recorded as zero.
974
TMJ DISCECTOMY VERSUS ARTHROSCOPY
Table 2. MODIFIED QUESTIONNAIRE USED FOR SUBJECTIVE ASSESSMENT OF IMPAIRED MANDIBULAR FUNCTION
Mandibular Function Impairment Questionnaire How Difficult is it for You to Manage the Following Because of the Pain and Impairment in Your Temporomandibular Joint (grade according to this)? 0—No trouble 1—Minor 2—Moderate 3—Severe 4—Impossible without help Socialize Work Speak Yawn To chew or take a bite of: Meat Apple French bread Data from Stegenga.14
Pain relief after surgery was considered satisfactory with a VAS score less than 2. Mandibular function at baseline and at follow-up was assessed using the mandibular function impairment index (MFIQ) recommended by Stegenga,14 with slight modifications (Table 2). Mandibular function was judged satisfactory when the MFIQ was less than 7 (maximum score of 1 on each item). Clinical examination at baseline and at follow-up included: 1. Maximum interincisal opening (measured with a ruler, cutoff point 35 mm)5 2. Maximum protrusion (measured with a ruler, cutoff point 5 mm)5 3. Clicking (on palpation with a finger or auscultation with a stethoscope)—present or not 4. Crepitation (on palpation with a finger or auscultation with a stethoscope)—present or not 5. Tenderness on lateral palpation of TMJ— present or not 6. Tenderness on palpation of jaw muscles (⬎2 muscles on same side)—present or not All recordings at baseline and at follow-up were performed by the same clinician (S.A.), a specialist in clinical oral physiology. STATISTICAL METHODS
The paired t-test was used to evaluate whether differences in scores for MFIQ and VAS between baseline and the 1-year follow-up were significant. The paired t-test and Wilcoxon matched pairs test were used to evaluate whether differences in scores for maximum opening and protrusion between baseline
and the 1-year follow-up were significant. The sign test was used to evaluate whether differences in scores for lateral joint tenderness, muscle tenderness, crepitation, and clicking between baseline and the 1-year follow-up were significant. A sample-size determination (“power analysis”) was also done 1-sided hypothesis, risk level 5%, and power 80%).
Results Because all 20 patients completed the study, the dropout rate was zero. The time between randomization and surgery was a mean of 1.6 months (range, 0.5 to 4) for arthroscopy and 1.3 months (range, 0.5 to 6) for discectomy. Only 1 patient in each group waited more than 4 months. No complications occurred during or after surgery. Although a small region of hyposensitivity was noted close to the incision in some patients in the discectomy group, they did not complain about it. No patient developed transient palsy of the facial nerve. The duration of surgery was a mean of 70 minutes for discectomy and 25 minutes for arthroscopic lysis and lavage (excluding preparation, etc). The sickleave varied between 2 and 3 weeks for discectomy and 0 and 3 days for arthroscopy. The individual and mean VAS scores for the arthroscopy and discectomy patients at baseline and at 1-year follow-up are shown in Table 3. The severity of pain intensity was significantly reduced in both groups (discectomy, P ⬍ .001; arthroscopy, P ⫽ .001). At the 1-year follow-up, 9 patients (90%) scored less than 2 on the VAS scale in the discectomy group compared with 5 patients (50%) in the arthroscopy group. The individual and mean MFIQ scores for the discectomy and arthroscopy patients at baseline and at the 1-year follow-up are shown in Table 4. At the
Table 3. VISUAL ANALOG ASSESSMENTS AT BASELINE AND 1-YEAR FOLLOW-UP
VAS Discectomy
Patient 1 2 3 4 5 6 7 8 9 10 Mean
Arthroscopy
Baseline
1 yr
Baseline
1 yr
9 7 8 4 7 9 6 8 4 0 6.2
1 4 0 0 1 0 0 0 0 0 0.6
8 8 8 6 7 7 7 7 8 5 7.1
3 6 0 0 5 9 0 2 0 0 2.5
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HOLMLUND, AXELSSON, AND GYNTHER
Table 4. REPLIES TO MANDIBULAR FUNCTION IMPAIRMENT QUESTIONNAIRE AT BASELINE AND 1-YEAR FOLLOW-UP
Mandibular Function Impairment Questionnaire Discectomy
Patient 1 2 3 4 5 6 7 8 9 10 Mean
Arthroscopy
Baseline
1 yr
Baseline
1 yr
24 16 15 20 13 20 12 15 12 11 15.8
5 4 0 6 8 4 0 3 8 11 4.9
15 13 20 12 11 18 8 12 16 20 14.5
7 5 3 1 6 22 4 1 9 4 6.2
1-year follow-up, 7 patients (70%) in both the discectomy and arthroscopy groups had a MFIQ score less than 7. Both the discectomy and arthroscopy patients showed significant improvement in mandibular function (discectomy, P ⬍ .001; arthroscopy, P ⫽ .002). The duration of locking before surgical intervention was a mean of 8.5 months (range, 2 to 24) in the discectomy patients and a mean of 20.5 months (range, 2 to 60) in the arthroscopy patients (Table 1). When patients in both groups were combined and those with locking for less than 6 months were compared to those who had locking for more than 6 months, there were no differences with regard to improvement in VAS and MFIQ. The clinical signs and symptoms at baseline and the 1-year follow-up are shown in Table 5. Both discectomy and arthroscopy patients showed significantly increased mouth opening at the 1-year follow-up (discectomy, P ⬍ .001; arthroscopy, P ⫽ .001). Using the cutoff point for maximum interincisal opening of more than 35 mm, 8 patients (80%) in both groups
fulfilled the criterion at the 1-year follow-up. Maximum protrusion had also increased in both groups of patients at the 1-year follow-up (discectomy, P ⫽ .049; arthroscopy, P ⫽ .041). Ten patients (100%) in the arthroscopy group and 8 patients (80%) in the discectomy group fulfilled the criterion of a cutoff point for maximum protrusion of more than 5 mm. In the discectomy patients, crepitation was found in 4 joints (40%) at the 1-year follow-up compared with 1 joint (10%) at baseline. In the arthroscopy patients, clicking was present in 3 joints (30%) at the 1-year follow-up compared with 1 joint (10%) at baseline. Both the discectomy and arthroscopy patients showed a reduction in joint tenderness at the 1-year follow-up. However, the difference was significant only in the discectomy patients (discectomy, P ⫽ .016; arthroscopy, P ⫽ .063, not significant). The determination of the sample size showed that 132 and 222 patients (equally distributed) would have been needed to detect significant differences between arthroscopic lysis and lavage versus discectomy regarding VAS and MFIQ.
Discussion Several prospective long-term studies have shown that discectomy effectively alleviates pain and improves mandibular function in patients with internal derangement of the TMJ.4-6 Therefore, it should be used for comparison with the newly introduced surgical methods. It is important to make such comparisons in a randomized fashion, with specific assessment criteria. In this study, only patients with unilateral chronic locking of the TMJ and no other TMJ disorders were included. The findings are therefore valid only for this group of patients. Admission of these patients to the study was based on clinical criteria alone. It may be said that imaging criteria, such as the position of the disc, should have been included. We did not do this because neither
Table 5. CLINICAL FINDINGS AT BASELINE AND 1-YEAR FOLLOW-UP
Discectomy (n ⫽ 10) Maximum opening (⬎35 mm) Protrusion (⬎5 mm) Crepitation Clicking Joint tenderness, lateral palpation Muscle tenderness (⬎2 ipsilateral)
Arthroscopy (n ⫽ 10)
Baseline
1 yr
Baseline
1 yr
1 5 1 0 8 4
8 8 4 0 1 0
2 6 1 1 6 3
8 10 1 3 1 1
976 soft tissue nor hard tissue imaging necessarily correlates with pain or even impaired mandibular function.15 Furthermore, a very high frequency of anterior disc position has been found in subjects without TMJ disease,16 which makes this criterion unreliable. A risk of subjective upgrading of postoperative clinical findings always exists if the surgeon also performs the postoperative evaluation. The pre- and postoperative assessments were therefore done by a specialist in clinical oral physiology who had experience in the nonsurgical treatment of TMJ disorders. The duration of the TMJ locking was longer in the arthroscopy patients mainly because 2 patients in that group had had this symptom for 60 months. Patients with pain for more than 6 months may develop chronic pain behavior. It is of note that we found no difference between patients having a duration of symptoms less than 6 months and those with a symptom duration of more than 6 months, nor was there a difference between discectomy and arthroscopy patients in this respect. The mean VAS and MFIQ scores at baseline for the discectomy and arthroscopy groups showed that patients with chronic locking rated their pain intensity and functional impairment as moderate to severe. Very few patients reported unbearable pain or impairment. This is in accord with the findings of Stegenga.17 It is therefore important to first treat patients with TMJ internal derangement nonsurgically. This was also done in the present study. Both discectomy and arthroscopy had significantly reduced the severity of pain at the 1-year follow-up. Using the cutoff point for a satisfactory result (VAS ⬍ 2), discectomy was more effective. However, no definite difference in lateral joint tenderness was found between discectomy and arthroscopy patients at the 1-year follow-up. On the MFIQ, both discectomy and arthroscopy resulted in significant improvement in mandibular function at the 1-year follow-up. The mean difference between baseline and 1-year follow-up scores was somewhat in favor of the discectomy patients. However, using the cutoff point for a satisfactory result (MFIQ ⬍7), no difference was found between the 2 groups. The scores for the clinical parameters (maximum opening and protrusion) at the 1-year follow-up also indicated similar good results with both methods. Crepitation is often present after surgery in TMJs subjected to discectomy.5 This was also true of 40% of these patients at the 1-year follow-up. This figure is lower than that reported elsewhere,5 but differed completely from the arthroscopy patients; none of whom had developed crepitation at the 1-year follow-up. One arthroscopy patient complained of slight clicking (not reciprocal) at baseline, which disappeared
TMJ DISCECTOMY VERSUS ARTHROSCOPY
after arthroscopy. Its cause could not be determined during the arthroscopic examination. Three arthroscopy patients had slight clicking in the operated TMJ at the 1-year follow-up, but none of them were bothered by it. Muscle pain was infrequent at the baseline examination and, if present, seemed to be reduced at the 1-year follow-up. The sample size for this study was rather small. However, when the sample size (“power analysis”) needed to detect significant differences between arthroscopic lysis and lavage versus discectomy was calculated, the number of patients would have had to be impracticably large. Our findings show that discectomy and arthroscopic lysis and lavage are effective methods for surgical treatment for chronic closed lock of the TMJ. Because arthroscopic lysis and lavage is a minimally invasive, oupatient procedure it seems appropriate to recommend it as the first choice for surgical treatment of chronic closed lock of the TMJ.
References 1. Lanz A: Discitis mandibularis. Zentralbl Chir 36:289, 1909 2. Poswillo DE: Conservative management of degenerative temporomandibular joint disease in the elderly. Int Dent J 33:325, 1983 3. Carlsson GE, Kopp S, Lindstro ¨ m J, et al: Surgical treatment of the temporomandibular joint. Swed Dent J 5:41, 1981 4. Eriksson L, Westesson P-L: Temporomandibular joint diskectomy: No positive effect of temporary silicone implant in a 5-year follow-up. Oral Surg Oral Med Oral Pathol 74:259, 1992 5. Holmlund AB, Gynther GW, Axelsson S: Diskectomy in treatment of internal derangement of the temporomandibular joint. Follow-up at 1, 3, and 5 years. Oral Surg Oral Med Oral Pathol 76:266, 1993 6. Widmark G, Dalstro ¨ m L, Kahnberg KE, et al: Diskectomy in temporomandibular joints with internal derangement: A follow-up study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 83:314, 1997 7. Widmark G, Grondahl HG, Kahnberg KE, et al: Radiographic morphology in the temporomandibular joint after diskectomy. Cranio 14:37, 1996 8. Ohnishi M: Arthroscopy of the temporomandibular joint (in Japanese). J Jpn Stomat 42:207, 1975 9. Sanders B: Arthroscopic surgery for the temporomandibular joint. Treatment of internal derangement with persistent closed lock. Oral Surg Oral Med Oral Pathol 62:361, 1986 10. Murakami K, Hosaka H, Moriya Y, et al: Short-term treatment outcome for the management of temporomandibular joint closed lock. A comparison of arthrocentesis to nonsurgical and arthroscopic lysis and lavage. Oral Surg Oral Med Oral Pathol 80:253, 1995 11. Fridrich KL, Wise JM, Zeitler DL: Prospective comparison of arthroscopy and arthrocentesis for temporomandibular joint disorders. J Oral Maxillofac Surg 54:816, 1996 12. Holmlund AB. Criteria for temporomandibular joint treatment outcome, in Stegenga B, de Bont LGM (eds): Management of Temporomandibular Joint Degenerative Diseases: Biological Basis and Treatment Outcome. Basel, Switzerland, Birkha¨user, 1996, p 63 13. Holmlund A, Gynther G, Axelsson S: Efficacy of arthroscopic lysis and lavage in patients with chronic locking of the temporomandibular joint. Int J Oral Maxillofac Surg 23:262, 1994 14. Stegenga B: Temporomandibular joint osteoarthrosis and inter-
977 nal derangement. Diagnostic and therapeutic outcome assessment [doctoral thesis] Groningen, The Netherlands, Drukkerij van Denderen BV, 1991, p 147 15. Montgommery MT, Van Sickels JE, Harms SE: Success of temporomandibular joint arthroscopy in disc displacement with and without reduction. Oral Surg Oral Med Oral Pathol 71:651, 1991
16. Kircos LT, Ortendahl DA, Mark AS, et al: Magnetic resonance imaging of the TMJ disc in asymptomatic volunteers. J Oral Maxillofac Surg 45:852, 1987 17. Stegenga B, de Bont LGM, Dijkstra PU, et al: Short-term outcome of arthroscopic surgery of temporomandibular joint osteoarthrosis and internal derangement: A randomized controlled clinical trial. Br J Oral Maxillofac Surg 31:93, 1993
A Comparison of Discectomy and Arthroscopic Lysis and Lavage for the Treatment of Chronic Closed Lock of the Temporomandibular Joint: A Randomized Outcome Study Anders B. Holmlund, DDS, PhD,* Susanna Axelsson, DDS, PhD,† and Go ¨ ran W. Gynther, DDS, PhD‡ Purpose:
The study compared the efficacy of discectomy or arthroscopic lysis and lavage in patients with chronic closed lock of the temporomandibular joint (TMJ) in a prospective, randomized clinical trial. Patients and Methods: Twenty-two patients with a clinical diagnosis of chronic closed lock were prospectively randomized to either discectomy or arthroscopic lysis and lavage. The individual outcome in each patient was evaluated with a visual analog scale for pain and a questionnaire concerning mandibular functional impairment. The clinical evaluation included measurement of maximum interincisal opening and protrusion, recording of clicking and crepitation, and palpation for tenderness of the TMJ and jaw muscles. Recordings were made before the operation (baseline) and at the 1-year follow-up. Results: Twenty patients completed the study. Discectomy and arthroscopic lysis and lavage significantly reduced pain and improved mandibular function. Discectomy reduced pain somewhat more effectively than arthroscopic lysis and lavage. The clinical recordings at the 1-year follow-up indicated similarly good outcomes after both procedures. Conclusion: Both discectomy and arthroscopic lysis and lavage are effective surgical methods for treatment of chronic closed lock of the TMJ. Considering that arthroscopic lysis and lavage is a minimally invasive outpatient procedure, it should be used as the first choice in surgical treatment of this condition. © 2001 American Association of Oral and Maxillofacial Surgeons Chronic closed lock of the temporomandibular joint (TMJ) is a common indication for surgery of the TMJ.
Several methods have been proposed and evaluated. The oldest is discectomy, which was introduced in 1909 by Lanz.1 Although disregarded by some,2,3 it has survived for almost a century and is still widely used. It has also been thoroughly assessed in clinical trials. Prospective long-term studies in 3 centers have all shown a stable outcome and a low incidence of complications even after a long period.4-6 However, removal of the disc also has some deleterious effects, such as radiographic signs of osteoarthrosis,7 clinically reflected by an increased frequency of crepitation.5 Furthermore, some patients develop fibrous adhesions, which limit mandibular movement. Arthroscopy of the TMJ was first reported by Ohnishi in 1975.8 In 1986, Sanders described a simple method for lysis and lavage of the TMJ.9 It has been widely used, and several investigators have reported on its efficacy and noninvasiveness.10,11 However,
*Professor and Consultant, Department of Oral and Maxillofacial Surgery, Institution of Odontology, Karolinska Institutet/Huddinge University Hospital, Huddinge, Sweden. †Project Director, The Swedish Council on Technology Assessment in Health Care, Stockholm, Sweden. ‡Associate Professor and Consultant, Department of Oral and Maxillofacial Surgery, Institution of Odontology, Karolinska Institutet/Huddinge University Hospital, Huddinge, Sweden. Address correspondence and reprint requests to Dr Holmlund: Department of Oral and Maxillofacial Surgery, Institution of Odontology, Karolinska Institutet, Box 4064, S-141 04 Huddinge, Sweden; e-mail: [email protected] © 2001 American Association of Oral and Maxillofacial Surgeons
0278-2391/01/5909-0002$35.00/0 doi:10.1053/joms.2001.25818
972
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HOLMLUND, AXELSSON, AND GYNTHER
Table 1. DEMOGRAPHIC FINDINGS IN THE PATIENTS
Discectomy (n ⫽ 10) Arthroscopy (n ⫽ 10)
Age (yr)
Female/Male (No.)
Left/Right Joint (No.)
Mean Duration of Locking (mo)
37 (22–53) 32 (22–46)
10/0 8/2
5/5 6/4
8.5 (2–24) 20.5 (2–60)
very few outcome studies of discectomy and arthroscopic lysis and lavage fulfill the criteria for proper assessment.12 Thus, dropout of patients, specific inclusion and exclusion criteria, and methods for evaluation have not been adequately described, which limits the scientific value of such studies. Furthermore, the comparative analyses are rarely randomized. We have previously proposed that discectomy should be a standard procedure for comparisons in randomized trials.5 However, our experience in patients with chronic closed lock of the TMJ has indicated that arthroscopic lysis and lavage also can be useful.13 Thus, the goal of the present study was to compare the clinical outcome of the latter method with that of discectomy in a randomized prospective trial.
Patients and Methods Twenty-four patients fulfilled the following inclusion criteria: 1) clinical diagnosis of chronic closed lock of the TMJ (previous clicking in the TMJ replaced by pain in the TMJ and limitation of vertical and horizontal mandibular movements); 2) unilateral involvement; and 3) unsuccessful nonsurgical treatment for at least 3 months. Exclusion criteria included other TMJ disease, major jaw trauma, or a dentofacial deformity. Twenty-four consecutive patients fulfilling the inclusion criteria were asked if they would participate in the randomized study. Two patients declined to participate. The remaining 22 patients were randomized to either discectomy or arthroscopic lysis and lavage. However, 2 of these 22 patients were excluded at the time of the study. Both patients had been randomized for arthroscopic lysis and lavage. One patient recovered spontaneously before arthroscopy was performed, and 1 patient, in whom arthroscopy had been performed, developed polyarthritis related to a Borrelia infection 3 months after arthroscopy. The remaining 20 patients comprised the study material. Their demographic characteristics are shown in Table 1. All patients received full information about both procedures and our intention to evaluate the efficacy in a randomized fashion. They were asked to consider
the information provided and then to give their consent. They were then randomized to either discectomy or arthroscopic lysis and lavage using a randomization format. Discectomy was performed under general anesthesia, according to a previously described method.5 The joint was exposed through a preauricular incision. After excision of the disc, any irregularities on the condyle were smoothed with a diamond file. No autogenous or alloplastic replacement materials were inserted. The patients were admitted to the hospital the day before surgery and were discharged the day after surgery. Antibiotic coverage was given preoperatively (a single dose of clindamycin 600 mg intravenously). The procedure for arthroscopic lysis and lavage has also been described elsewhere.13 An inferolateral approach was used for trocar puncture, and an outflow needle was placed through the skin 5 mm anterior to and slightly below the entry of the trocar. The upper compartment of the TMJ was examined with a 30° telescope (Karl Storz GmbH & Co, Tuttlingen, Germany). Any fibrous adhesions were released in a semiblind fashion using a blunt trocar. The upper compartment was then irrigated with 100 mL isotonic saline solution, using the outflow needle for injection and the arthroscopic cannula for outflow. After arthroscopy, the patient remained in the clinic for about 1 hour to recover before being discharged. All arthroscopic procedures were performed in the outpatient clinic under local anesthesia and intravenous sedation with a short-acting benzodiazepine (midazolam). No antibiotic coverage or steroid injections were given. The surgical procedures were performed by 2 oral and maxillofacial surgeons (A.B.H. and G.W.G.), who worked in the same department and were carefully calibrated regarding the inclusion and exclusion criteria and the surgical technique. Pain in the TMJ on mandibular function (opening the mouth, chewing, biting, yawning) was recorded at baseline (the day before surgery) and at follow-up (3 months and 1 year) using a 10-cm visual analog scale (VAS). The scale was divided into 10 fields and, if pain was present, the patient was asked to select a field from 1 to 10. If there was no pain, it was recorded as zero.
974
TMJ DISCECTOMY VERSUS ARTHROSCOPY
Table 2. MODIFIED QUESTIONNAIRE USED FOR SUBJECTIVE ASSESSMENT OF IMPAIRED MANDIBULAR FUNCTION
Mandibular Function Impairment Questionnaire How Difficult is it for You to Manage the Following Because of the Pain and Impairment in Your Temporomandibular Joint (grade according to this)? 0—No trouble 1—Minor 2—Moderate 3—Severe 4—Impossible without help Socialize Work Speak Yawn To chew or take a bite of: Meat Apple French bread Data from Stegenga.14
Pain relief after surgery was considered satisfactory with a VAS score less than 2. Mandibular function at baseline and at follow-up was assessed using the mandibular function impairment index (MFIQ) recommended by Stegenga,14 with slight modifications (Table 2). Mandibular function was judged satisfactory when the MFIQ was less than 7 (maximum score of 1 on each item). Clinical examination at baseline and at follow-up included: 1. Maximum interincisal opening (measured with a ruler, cutoff point 35 mm)5 2. Maximum protrusion (measured with a ruler, cutoff point 5 mm)5 3. Clicking (on palpation with a finger or auscultation with a stethoscope)—present or not 4. Crepitation (on palpation with a finger or auscultation with a stethoscope)—present or not 5. Tenderness on lateral palpation of TMJ— present or not 6. Tenderness on palpation of jaw muscles (⬎2 muscles on same side)—present or not All recordings at baseline and at follow-up were performed by the same clinician (S.A.), a specialist in clinical oral physiology. STATISTICAL METHODS
The paired t-test was used to evaluate whether differences in scores for MFIQ and VAS between baseline and the 1-year follow-up were significant. The paired t-test and Wilcoxon matched pairs test were used to evaluate whether differences in scores for maximum opening and protrusion between baseline
and the 1-year follow-up were significant. The sign test was used to evaluate whether differences in scores for lateral joint tenderness, muscle tenderness, crepitation, and clicking between baseline and the 1-year follow-up were significant. A sample-size determination (“power analysis”) was also done 1-sided hypothesis, risk level 5%, and power 80%).
Results Because all 20 patients completed the study, the dropout rate was zero. The time between randomization and surgery was a mean of 1.6 months (range, 0.5 to 4) for arthroscopy and 1.3 months (range, 0.5 to 6) for discectomy. Only 1 patient in each group waited more than 4 months. No complications occurred during or after surgery. Although a small region of hyposensitivity was noted close to the incision in some patients in the discectomy group, they did not complain about it. No patient developed transient palsy of the facial nerve. The duration of surgery was a mean of 70 minutes for discectomy and 25 minutes for arthroscopic lysis and lavage (excluding preparation, etc). The sickleave varied between 2 and 3 weeks for discectomy and 0 and 3 days for arthroscopy. The individual and mean VAS scores for the arthroscopy and discectomy patients at baseline and at 1-year follow-up are shown in Table 3. The severity of pain intensity was significantly reduced in both groups (discectomy, P ⬍ .001; arthroscopy, P ⫽ .001). At the 1-year follow-up, 9 patients (90%) scored less than 2 on the VAS scale in the discectomy group compared with 5 patients (50%) in the arthroscopy group. The individual and mean MFIQ scores for the discectomy and arthroscopy patients at baseline and at the 1-year follow-up are shown in Table 4. At the
Table 3. VISUAL ANALOG ASSESSMENTS AT BASELINE AND 1-YEAR FOLLOW-UP
VAS Discectomy
Patient 1 2 3 4 5 6 7 8 9 10 Mean
Arthroscopy
Baseline
1 yr
Baseline
1 yr
9 7 8 4 7 9 6 8 4 0 6.2
1 4 0 0 1 0 0 0 0 0 0.6
8 8 8 6 7 7 7 7 8 5 7.1
3 6 0 0 5 9 0 2 0 0 2.5
975
HOLMLUND, AXELSSON, AND GYNTHER
Table 4. REPLIES TO MANDIBULAR FUNCTION IMPAIRMENT QUESTIONNAIRE AT BASELINE AND 1-YEAR FOLLOW-UP
Mandibular Function Impairment Questionnaire Discectomy
Patient 1 2 3 4 5 6 7 8 9 10 Mean
Arthroscopy
Baseline
1 yr
Baseline
1 yr
24 16 15 20 13 20 12 15 12 11 15.8
5 4 0 6 8 4 0 3 8 11 4.9
15 13 20 12 11 18 8 12 16 20 14.5
7 5 3 1 6 22 4 1 9 4 6.2
1-year follow-up, 7 patients (70%) in both the discectomy and arthroscopy groups had a MFIQ score less than 7. Both the discectomy and arthroscopy patients showed significant improvement in mandibular function (discectomy, P ⬍ .001; arthroscopy, P ⫽ .002). The duration of locking before surgical intervention was a mean of 8.5 months (range, 2 to 24) in the discectomy patients and a mean of 20.5 months (range, 2 to 60) in the arthroscopy patients (Table 1). When patients in both groups were combined and those with locking for less than 6 months were compared to those who had locking for more than 6 months, there were no differences with regard to improvement in VAS and MFIQ. The clinical signs and symptoms at baseline and the 1-year follow-up are shown in Table 5. Both discectomy and arthroscopy patients showed significantly increased mouth opening at the 1-year follow-up (discectomy, P ⬍ .001; arthroscopy, P ⫽ .001). Using the cutoff point for maximum interincisal opening of more than 35 mm, 8 patients (80%) in both groups
fulfilled the criterion at the 1-year follow-up. Maximum protrusion had also increased in both groups of patients at the 1-year follow-up (discectomy, P ⫽ .049; arthroscopy, P ⫽ .041). Ten patients (100%) in the arthroscopy group and 8 patients (80%) in the discectomy group fulfilled the criterion of a cutoff point for maximum protrusion of more than 5 mm. In the discectomy patients, crepitation was found in 4 joints (40%) at the 1-year follow-up compared with 1 joint (10%) at baseline. In the arthroscopy patients, clicking was present in 3 joints (30%) at the 1-year follow-up compared with 1 joint (10%) at baseline. Both the discectomy and arthroscopy patients showed a reduction in joint tenderness at the 1-year follow-up. However, the difference was significant only in the discectomy patients (discectomy, P ⫽ .016; arthroscopy, P ⫽ .063, not significant). The determination of the sample size showed that 132 and 222 patients (equally distributed) would have been needed to detect significant differences between arthroscopic lysis and lavage versus discectomy regarding VAS and MFIQ.
Discussion Several prospective long-term studies have shown that discectomy effectively alleviates pain and improves mandibular function in patients with internal derangement of the TMJ.4-6 Therefore, it should be used for comparison with the newly introduced surgical methods. It is important to make such comparisons in a randomized fashion, with specific assessment criteria. In this study, only patients with unilateral chronic locking of the TMJ and no other TMJ disorders were included. The findings are therefore valid only for this group of patients. Admission of these patients to the study was based on clinical criteria alone. It may be said that imaging criteria, such as the position of the disc, should have been included. We did not do this because neither
Table 5. CLINICAL FINDINGS AT BASELINE AND 1-YEAR FOLLOW-UP
Discectomy (n ⫽ 10) Maximum opening (⬎35 mm) Protrusion (⬎5 mm) Crepitation Clicking Joint tenderness, lateral palpation Muscle tenderness (⬎2 ipsilateral)
Arthroscopy (n ⫽ 10)
Baseline
1 yr
Baseline
1 yr
1 5 1 0 8 4
8 8 4 0 1 0
2 6 1 1 6 3
8 10 1 3 1 1
976 soft tissue nor hard tissue imaging necessarily correlates with pain or even impaired mandibular function.15 Furthermore, a very high frequency of anterior disc position has been found in subjects without TMJ disease,16 which makes this criterion unreliable. A risk of subjective upgrading of postoperative clinical findings always exists if the surgeon also performs the postoperative evaluation. The pre- and postoperative assessments were therefore done by a specialist in clinical oral physiology who had experience in the nonsurgical treatment of TMJ disorders. The duration of the TMJ locking was longer in the arthroscopy patients mainly because 2 patients in that group had had this symptom for 60 months. Patients with pain for more than 6 months may develop chronic pain behavior. It is of note that we found no difference between patients having a duration of symptoms less than 6 months and those with a symptom duration of more than 6 months, nor was there a difference between discectomy and arthroscopy patients in this respect. The mean VAS and MFIQ scores at baseline for the discectomy and arthroscopy groups showed that patients with chronic locking rated their pain intensity and functional impairment as moderate to severe. Very few patients reported unbearable pain or impairment. This is in accord with the findings of Stegenga.17 It is therefore important to first treat patients with TMJ internal derangement nonsurgically. This was also done in the present study. Both discectomy and arthroscopy had significantly reduced the severity of pain at the 1-year follow-up. Using the cutoff point for a satisfactory result (VAS ⬍ 2), discectomy was more effective. However, no definite difference in lateral joint tenderness was found between discectomy and arthroscopy patients at the 1-year follow-up. On the MFIQ, both discectomy and arthroscopy resulted in significant improvement in mandibular function at the 1-year follow-up. The mean difference between baseline and 1-year follow-up scores was somewhat in favor of the discectomy patients. However, using the cutoff point for a satisfactory result (MFIQ ⬍7), no difference was found between the 2 groups. The scores for the clinical parameters (maximum opening and protrusion) at the 1-year follow-up also indicated similar good results with both methods. Crepitation is often present after surgery in TMJs subjected to discectomy.5 This was also true of 40% of these patients at the 1-year follow-up. This figure is lower than that reported elsewhere,5 but differed completely from the arthroscopy patients; none of whom had developed crepitation at the 1-year follow-up. One arthroscopy patient complained of slight clicking (not reciprocal) at baseline, which disappeared
TMJ DISCECTOMY VERSUS ARTHROSCOPY
after arthroscopy. Its cause could not be determined during the arthroscopic examination. Three arthroscopy patients had slight clicking in the operated TMJ at the 1-year follow-up, but none of them were bothered by it. Muscle pain was infrequent at the baseline examination and, if present, seemed to be reduced at the 1-year follow-up. The sample size for this study was rather small. However, when the sample size (“power analysis”) needed to detect significant differences between arthroscopic lysis and lavage versus discectomy was calculated, the number of patients would have had to be impracticably large. Our findings show that discectomy and arthroscopic lysis and lavage are effective methods for surgical treatment for chronic closed lock of the TMJ. Because arthroscopic lysis and lavage is a minimally invasive, oupatient procedure it seems appropriate to recommend it as the first choice for surgical treatment of chronic closed lock of the TMJ.
References 1. Lanz A: Discitis mandibularis. Zentralbl Chir 36:289, 1909 2. Poswillo DE: Conservative management of degenerative temporomandibular joint disease in the elderly. Int Dent J 33:325, 1983 3. Carlsson GE, Kopp S, Lindstro ¨ m J, et al: Surgical treatment of the temporomandibular joint. Swed Dent J 5:41, 1981 4. Eriksson L, Westesson P-L: Temporomandibular joint diskectomy: No positive effect of temporary silicone implant in a 5-year follow-up. Oral Surg Oral Med Oral Pathol 74:259, 1992 5. Holmlund AB, Gynther GW, Axelsson S: Diskectomy in treatment of internal derangement of the temporomandibular joint. Follow-up at 1, 3, and 5 years. Oral Surg Oral Med Oral Pathol 76:266, 1993 6. Widmark G, Dalstro ¨ m L, Kahnberg KE, et al: Diskectomy in temporomandibular joints with internal derangement: A follow-up study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 83:314, 1997 7. Widmark G, Grondahl HG, Kahnberg KE, et al: Radiographic morphology in the temporomandibular joint after diskectomy. Cranio 14:37, 1996 8. Ohnishi M: Arthroscopy of the temporomandibular joint (in Japanese). J Jpn Stomat 42:207, 1975 9. Sanders B: Arthroscopic surgery for the temporomandibular joint. Treatment of internal derangement with persistent closed lock. Oral Surg Oral Med Oral Pathol 62:361, 1986 10. Murakami K, Hosaka H, Moriya Y, et al: Short-term treatment outcome for the management of temporomandibular joint closed lock. A comparison of arthrocentesis to nonsurgical and arthroscopic lysis and lavage. Oral Surg Oral Med Oral Pathol 80:253, 1995 11. Fridrich KL, Wise JM, Zeitler DL: Prospective comparison of arthroscopy and arthrocentesis for temporomandibular joint disorders. J Oral Maxillofac Surg 54:816, 1996 12. Holmlund AB. Criteria for temporomandibular joint treatment outcome, in Stegenga B, de Bont LGM (eds): Management of Temporomandibular Joint Degenerative Diseases: Biological Basis and Treatment Outcome. Basel, Switzerland, Birkha¨user, 1996, p 63 13. Holmlund A, Gynther G, Axelsson S: Efficacy of arthroscopic lysis and lavage in patients with chronic locking of the temporomandibular joint. Int J Oral Maxillofac Surg 23:262, 1994 14. Stegenga B: Temporomandibular joint osteoarthrosis and inter-
977 nal derangement. Diagnostic and therapeutic outcome assessment [doctoral thesis] Groningen, The Netherlands, Drukkerij van Denderen BV, 1991, p 147 15. Montgommery MT, Van Sickels JE, Harms SE: Success of temporomandibular joint arthroscopy in disc displacement with and without reduction. Oral Surg Oral Med Oral Pathol 71:651, 1991
16. Kircos LT, Ortendahl DA, Mark AS, et al: Magnetic resonance imaging of the TMJ disc in asymptomatic volunteers. J Oral Maxillofac Surg 45:852, 1987 17. Stegenga B, de Bont LGM, Dijkstra PU, et al: Short-term outcome of arthroscopic surgery of temporomandibular joint osteoarthrosis and internal derangement: A randomized controlled clinical trial. Br J Oral Maxillofac Surg 31:93, 1993