- Email: [email protected]
Instrument for lateral release in temporomandibular joint hypomobility
Vol. 89 No. 4 April 2000
ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY CLINICAL NOTES Instrument for lateral release in temporomandibular joint hypomobility Koji Kino, DDS, PhD,a Tomoaki Shibuya, DDS, PhD,b Hiroyuki Yoshitake, DDS,c Teruo Amagasa, DDS, PhDd, Hakubun Yonezu, DDS, PhD,e and Masashi Sugisaki, DDS, PhD,f Tokyo, Japan TOKYO MEDICAL AND DENTAL UNIVERSITY, TOKYO DENTAL COLLEGE, AND JIKEI UNIVERSITY SCHOOL OF MEDICINE
(Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;89:398-401)
Since the first report of arthroscopy of the temporomandibular joint (TMJ) by Ohnishi,1 intervention by arthroscopic examination and surgery have become popular worldwide for treating TMJ disorders. The investigators of many studies have reported that arthroscopic sweep, lysis, and lavage improve joint function and relieve the pain caused by persistent closed lock of the TMJ.2 There are a few reports of lateral release and stretching of the capsule. Ohnishi1 was the first to report the use of arthroscopy to show adhesive tissue in the lateral region of the upper joint cavity. Murakami et al3 and Moses and Poker4 suggested the importance of the capsular stretch procedure or capsular release for joint mobility. Although previous reports suggested that lateral lysis and stretching of the lateral capsule aAssistant Professor, Maxillofacial Surgery, Maxillofacial Reconstruction and Function, Division of Maxillofacial and Neck Reconstruction, Graduate School, Tokyo Medical and Dental University. bResearch fellow, Maxillofacial Surgery, Maxillofacial Reconstruction and Function, Division of Maxillofacial and Neck Reconstruction, Graduate School, Tokyo Medical and Dental University. cGraduate student, Maxillofacial Surgery, Maxillofacial Reconstruction and Function, Division of Maxillofacial and Neck Reconstruction, Graduate School, Tokyo Medical and Dental University. dProfessor, Maxillofacial Surgery, Maxillofacial Reconstruction and Function, Division of Maxillofacial and Neck Reconstruction, Graduate School, Tokyo Medical and Dental University. eAssistant Professor, The Second Department of Oral and Maxillofacial Surgery, Tokyo Dental College. fAssociate Professor, Department of Dentistry, Jikei University School of Medicine. Received for publication July 28, 1999; returned for revision Sept 13, 1999; accepted for publication Oct 12, 1999. Copyright © 2000 by Mosby, Inc. 1079-2104/2000/$12.00 + 0 7/12/103669 doi:10.1067/moe.2000.103669
398
could be useful for increasing condylar mobility, capsular stretch was difficult to perform under arthroscopy. Problems included breakage of instruments and operating within a narrow joint space. Instrument breakage results from the more powerful force needed for the capsular stretch procedure than for lysis of band-like adhesive tissue. This capsular stretch had been performed by pulling the trocar with a cannula first in an outward direction, then in an upward direction. Because it was difficult to insert a solid and thick instrument into the narrow joint space for lateral release with an arthroscope, we have had to perform this procedure without an arthroscope, that is, working blind. We report the development of a new instrument to improve the safety of performing either a blind lateral release or lateral stretch within the TMJ.
Design of the lateral releaser First we had to develop a new stretching instrument that was strong enough to oppose the stretching force and able to be inserted not through a cannula, but directly from the entry point of the skin, and handled blindly. In the blind procedure, cautious handling of an instrument is necessary to prevent injuring the articular surface and surrounding tissue of the TMJ. The surface of the instrument must therefore be smooth. Also, because it will not be inserted through a cannula, the instrument must be of a shape that allows it to be easily inserted into the joint cavity to perform the lateral stretch. We designed and constructed a suitable instrument, which we termed a lateral releaser. The lateral releaser (Fig 1) should be given the following forms and conditions: 1. Enough strength for the hand force used for stretching
Kino et al 399
ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY Volume 89, Number 4
Fig 1. Lateral releaser.
Fig 2. Tip is turned to posterior slope of eminence, then moved along tubercle to lateral wall.
2. A shape suitable for approaching the lateral wall of the upper joint cavity from the entry point 3. A shape suitable for stretching the constricted lateral wall of the cavity 4. A smooth surface to prevent damaging tissue of the inner surface of the joint cavity 5. A mark on the handgrip to indicate the direction of the tip. To ensure that the instrument was strong enough, it was made with a diameter of 4.5 mm. To provide the
correct shape, the releaser was slightly bent biangularly about 20 degrees and provided with a handgrip. So it would stretch rather than damage the lateral wall, the tip of the instrument was made flat and blunt so it resembled an elevator used for fracture cases. The curved form of the tip allowed the instrument to be palpated on the covering skin surface during the stretching procedure.
Technique for handling the lateral releaser Arthroscopic inspection is generally performed
400 Kino et al
ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY April 2000
Fig 3. Releasing maneuver, demonstrated on left TMJ (posterolateral view). A, Lateral adhesion; D, articular disk; F, mandibular fossa; C, mandibular condyle.
before the lateral release and stretch. It is done with the patient under nasotracheal general anesthesia and by making a single puncture through the skin incision on the corresponding upper ridge of the mandibular fossa. After inspection and lysis of the joint space and removal of the arthroscopic cannula, the tip of the lateral releaser is inserted though the incision in a downward direction away from the patient’s head. The tip is pushed around the outer ridge of the glenoid fossa and inserted into the joint cavity. At the insertion of the releaser, the patient’s condyle is positioned as anteriorly as possible by the assistant operator to create space for the tip of the instrument. After the insertion, the condyle is positioned in the fossa and is then accessible for the procedure. During this step, the tip should not be inserted too deeply into the cavity to avoid injuring the roof of the fossa that separates the joint from the middle cranial fossa.5 The tip is then directed to the eminence and moved toward the tubercle along
the articular surface of the eminence (Fig 2). When a resistant sensation is perceived on the tip, stretching movement by the tip is repeated outward, then upward along the surface of the tubercle (Fig 3). After several stretches, the condylar movement and the inter-incisal mouth-opening range are inspected. This surgical maneuver and the inspection of condylar mobility should be repeated. It may be impossible to insert the lateral releaser perpendicularly to the zygomatic arch because of narrowness of the joint cavity caused by the constriction of the lateral wall. If so, the blunt blade of the tip could be inserted parallel to the articular surface of the posterior slope of the eminence. After attainment of a sufficient range of mouth-opening movement, the joint cavity is again observed by arthroscopy and washed with physiologic saline solution, and the skin incision is sutured. The joint cavity can be expanded by this procedure and the arthroscopic view field widened. If an adhesion is detected at other regions of the joint
ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY Volume 89, Number 4
Kino et al 401
cavity by the arthroscopic inspection, an additional lysis and release is done.
the condyle is attained by the surgery. Diskectomy might be applied in such cases.
DISCUSSION Persistent restricted movement of the TMJ probably makes the lateral wall less extensible. Some researchers 2,3 have suggested the importance of lateral stretch and release for condylar mobility. Two anatomic structural characteristics might explain the reason that the condylar movement is improved by this procedure despite displacement of the disk: (1) The articular disk is attached mainly to the lateral and medial pole of the condyle and has no intense fibrous attachment to the temporal bone, or (2) the condyle is suspended from the temporal bone with the lateral ligament bilaterally, but the diskal fibers are not combined with the lateral ligament.6 Thus the condyle and disk are able to swing back and forth as one unit. If the flexibility of the lateral wall involving the lateral ligament recovers, it follows that the condyle and the disk will be able to move more easily. For multiple adhesions or extensive fibrous change in the joint cavity, this procedure may not exert a lasting effect, even when temporal mobility of
REFERENCES 1. Ohnishi M. [Arthroscopy of the temporomandibular joint]. J Stomatol Soc Jpn 1975;42:207-13. (Jpn). 2. Ohnishi M, Misawa T, Kino K, Izumi Y, Ohmura Y, Kurokawa E. [Arthroscopic surgery for fibrous adhesion in the temporomandibular joint]. Arthroscopy. 1983;8:31-6. (Jpn). 3. Murakami K, Matsuki M, Tokuchi M, Tsukamoto Y, Iizuka T. [Arthroscopic sweep with lysis and lavage for internal derangement of the temporomandibular joint]. Jpn J Oral Maxillofac Surg 1988;34:1140-7. (Jpn). 4. Moses JJ, Poker ID. TMJ arthroscopic surgery: an analysis of 237 patients. J Oral Maxillofac Surg 1989;47:790-4. 5. Sugisaki M, Ikai A, Tanabe H. Dangerous angles and depths for middle ear and middle cranial fossa injury during arthroscopy of the temporomandibular joint. J Oral Maxillofac Surg 1995;53:80310. 6. Ohmura Y. [Histological observation on the structure of the lateral wall of the human temporomandibular joint]. J Stomatol Soc Japan 1984;51:465-92. (Jpn). Reprint requests: Koji Kino, DDS, PhD Maxillofacial Surgery Tokyo Medical and Dental University 1-5-45, Yushima, Bunkyo-ku Tokyo, 113-8549, Japan
CALL FOR LETTERS TO THE EDITOR A separate and distinct space for Letters to the Editor was established by Larry J. Peterson, editor in chief of Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics in his Editorial in the January 1993 issue. Dr Peterson also encouraged brief reports on interesting observations and new developments to be submitted to appear in this letters section as well as Letters commenting on earlier published articles. Please submit your letters and brief reports for inclusion in this section. Information for authors for the Journal appears in this issue of Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics. We look forward to hearing from you.
ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY CLINICAL NOTES Instrument for lateral release in temporomandibular joint hypomobility Koji Kino, DDS, PhD,a Tomoaki Shibuya, DDS, PhD,b Hiroyuki Yoshitake, DDS,c Teruo Amagasa, DDS, PhDd, Hakubun Yonezu, DDS, PhD,e and Masashi Sugisaki, DDS, PhD,f Tokyo, Japan TOKYO MEDICAL AND DENTAL UNIVERSITY, TOKYO DENTAL COLLEGE, AND JIKEI UNIVERSITY SCHOOL OF MEDICINE
(Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;89:398-401)
Since the first report of arthroscopy of the temporomandibular joint (TMJ) by Ohnishi,1 intervention by arthroscopic examination and surgery have become popular worldwide for treating TMJ disorders. The investigators of many studies have reported that arthroscopic sweep, lysis, and lavage improve joint function and relieve the pain caused by persistent closed lock of the TMJ.2 There are a few reports of lateral release and stretching of the capsule. Ohnishi1 was the first to report the use of arthroscopy to show adhesive tissue in the lateral region of the upper joint cavity. Murakami et al3 and Moses and Poker4 suggested the importance of the capsular stretch procedure or capsular release for joint mobility. Although previous reports suggested that lateral lysis and stretching of the lateral capsule aAssistant Professor, Maxillofacial Surgery, Maxillofacial Reconstruction and Function, Division of Maxillofacial and Neck Reconstruction, Graduate School, Tokyo Medical and Dental University. bResearch fellow, Maxillofacial Surgery, Maxillofacial Reconstruction and Function, Division of Maxillofacial and Neck Reconstruction, Graduate School, Tokyo Medical and Dental University. cGraduate student, Maxillofacial Surgery, Maxillofacial Reconstruction and Function, Division of Maxillofacial and Neck Reconstruction, Graduate School, Tokyo Medical and Dental University. dProfessor, Maxillofacial Surgery, Maxillofacial Reconstruction and Function, Division of Maxillofacial and Neck Reconstruction, Graduate School, Tokyo Medical and Dental University. eAssistant Professor, The Second Department of Oral and Maxillofacial Surgery, Tokyo Dental College. fAssociate Professor, Department of Dentistry, Jikei University School of Medicine. Received for publication July 28, 1999; returned for revision Sept 13, 1999; accepted for publication Oct 12, 1999. Copyright © 2000 by Mosby, Inc. 1079-2104/2000/$12.00 + 0 7/12/103669 doi:10.1067/moe.2000.103669
398
could be useful for increasing condylar mobility, capsular stretch was difficult to perform under arthroscopy. Problems included breakage of instruments and operating within a narrow joint space. Instrument breakage results from the more powerful force needed for the capsular stretch procedure than for lysis of band-like adhesive tissue. This capsular stretch had been performed by pulling the trocar with a cannula first in an outward direction, then in an upward direction. Because it was difficult to insert a solid and thick instrument into the narrow joint space for lateral release with an arthroscope, we have had to perform this procedure without an arthroscope, that is, working blind. We report the development of a new instrument to improve the safety of performing either a blind lateral release or lateral stretch within the TMJ.
Design of the lateral releaser First we had to develop a new stretching instrument that was strong enough to oppose the stretching force and able to be inserted not through a cannula, but directly from the entry point of the skin, and handled blindly. In the blind procedure, cautious handling of an instrument is necessary to prevent injuring the articular surface and surrounding tissue of the TMJ. The surface of the instrument must therefore be smooth. Also, because it will not be inserted through a cannula, the instrument must be of a shape that allows it to be easily inserted into the joint cavity to perform the lateral stretch. We designed and constructed a suitable instrument, which we termed a lateral releaser. The lateral releaser (Fig 1) should be given the following forms and conditions: 1. Enough strength for the hand force used for stretching
Kino et al 399
ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY Volume 89, Number 4
Fig 1. Lateral releaser.
Fig 2. Tip is turned to posterior slope of eminence, then moved along tubercle to lateral wall.
2. A shape suitable for approaching the lateral wall of the upper joint cavity from the entry point 3. A shape suitable for stretching the constricted lateral wall of the cavity 4. A smooth surface to prevent damaging tissue of the inner surface of the joint cavity 5. A mark on the handgrip to indicate the direction of the tip. To ensure that the instrument was strong enough, it was made with a diameter of 4.5 mm. To provide the
correct shape, the releaser was slightly bent biangularly about 20 degrees and provided with a handgrip. So it would stretch rather than damage the lateral wall, the tip of the instrument was made flat and blunt so it resembled an elevator used for fracture cases. The curved form of the tip allowed the instrument to be palpated on the covering skin surface during the stretching procedure.
Technique for handling the lateral releaser Arthroscopic inspection is generally performed
400 Kino et al
ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY April 2000
Fig 3. Releasing maneuver, demonstrated on left TMJ (posterolateral view). A, Lateral adhesion; D, articular disk; F, mandibular fossa; C, mandibular condyle.
before the lateral release and stretch. It is done with the patient under nasotracheal general anesthesia and by making a single puncture through the skin incision on the corresponding upper ridge of the mandibular fossa. After inspection and lysis of the joint space and removal of the arthroscopic cannula, the tip of the lateral releaser is inserted though the incision in a downward direction away from the patient’s head. The tip is pushed around the outer ridge of the glenoid fossa and inserted into the joint cavity. At the insertion of the releaser, the patient’s condyle is positioned as anteriorly as possible by the assistant operator to create space for the tip of the instrument. After the insertion, the condyle is positioned in the fossa and is then accessible for the procedure. During this step, the tip should not be inserted too deeply into the cavity to avoid injuring the roof of the fossa that separates the joint from the middle cranial fossa.5 The tip is then directed to the eminence and moved toward the tubercle along
the articular surface of the eminence (Fig 2). When a resistant sensation is perceived on the tip, stretching movement by the tip is repeated outward, then upward along the surface of the tubercle (Fig 3). After several stretches, the condylar movement and the inter-incisal mouth-opening range are inspected. This surgical maneuver and the inspection of condylar mobility should be repeated. It may be impossible to insert the lateral releaser perpendicularly to the zygomatic arch because of narrowness of the joint cavity caused by the constriction of the lateral wall. If so, the blunt blade of the tip could be inserted parallel to the articular surface of the posterior slope of the eminence. After attainment of a sufficient range of mouth-opening movement, the joint cavity is again observed by arthroscopy and washed with physiologic saline solution, and the skin incision is sutured. The joint cavity can be expanded by this procedure and the arthroscopic view field widened. If an adhesion is detected at other regions of the joint
ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY Volume 89, Number 4
Kino et al 401
cavity by the arthroscopic inspection, an additional lysis and release is done.
the condyle is attained by the surgery. Diskectomy might be applied in such cases.
DISCUSSION Persistent restricted movement of the TMJ probably makes the lateral wall less extensible. Some researchers 2,3 have suggested the importance of lateral stretch and release for condylar mobility. Two anatomic structural characteristics might explain the reason that the condylar movement is improved by this procedure despite displacement of the disk: (1) The articular disk is attached mainly to the lateral and medial pole of the condyle and has no intense fibrous attachment to the temporal bone, or (2) the condyle is suspended from the temporal bone with the lateral ligament bilaterally, but the diskal fibers are not combined with the lateral ligament.6 Thus the condyle and disk are able to swing back and forth as one unit. If the flexibility of the lateral wall involving the lateral ligament recovers, it follows that the condyle and the disk will be able to move more easily. For multiple adhesions or extensive fibrous change in the joint cavity, this procedure may not exert a lasting effect, even when temporal mobility of
REFERENCES 1. Ohnishi M. [Arthroscopy of the temporomandibular joint]. J Stomatol Soc Jpn 1975;42:207-13. (Jpn). 2. Ohnishi M, Misawa T, Kino K, Izumi Y, Ohmura Y, Kurokawa E. [Arthroscopic surgery for fibrous adhesion in the temporomandibular joint]. Arthroscopy. 1983;8:31-6. (Jpn). 3. Murakami K, Matsuki M, Tokuchi M, Tsukamoto Y, Iizuka T. [Arthroscopic sweep with lysis and lavage for internal derangement of the temporomandibular joint]. Jpn J Oral Maxillofac Surg 1988;34:1140-7. (Jpn). 4. Moses JJ, Poker ID. TMJ arthroscopic surgery: an analysis of 237 patients. J Oral Maxillofac Surg 1989;47:790-4. 5. Sugisaki M, Ikai A, Tanabe H. Dangerous angles and depths for middle ear and middle cranial fossa injury during arthroscopy of the temporomandibular joint. J Oral Maxillofac Surg 1995;53:80310. 6. Ohmura Y. [Histological observation on the structure of the lateral wall of the human temporomandibular joint]. J Stomatol Soc Japan 1984;51:465-92. (Jpn). Reprint requests: Koji Kino, DDS, PhD Maxillofacial Surgery Tokyo Medical and Dental University 1-5-45, Yushima, Bunkyo-ku Tokyo, 113-8549, Japan
CALL FOR LETTERS TO THE EDITOR A separate and distinct space for Letters to the Editor was established by Larry J. Peterson, editor in chief of Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics in his Editorial in the January 1993 issue. Dr Peterson also encouraged brief reports on interesting observations and new developments to be submitted to appear in this letters section as well as Letters commenting on earlier published articles. Please submit your letters and brief reports for inclusion in this section. Information for authors for the Journal appears in this issue of Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics. We look forward to hearing from you.